Vulnerability-Lookup

CVE-2026-24850 (GCVE-0-2026-24850)

Vulnerability from cvelistv5 – Published: 2026-01-28 00:24 – Updated: 2026-01-28 14:54

Title

ML-DSA Signature Verification Accepts Signatures with Repeated Hint Indices

Summary

The ML-DSA crate is a Rust implementation of the Module-Lattice-Based Digital Signature Standard (ML-DSA). Starting in version 0.0.4 and prior to version 0.1.0-rc.4, the ML-DSA signature verification implementation in the RustCrypto `ml-dsa` crate incorrectly accepts signatures with repeated (duplicate) hint indices. According to the ML-DSA specification (FIPS 204 / RFC 9881), hint indices within each polynomial must be **strictly increasing**. The current implementation uses a non-strict monotonic check (`<=` instead of `<`), allowing duplicate indices. This is a regression bug. The original implementation was correct, but a commit in version 0.0.4 inadvertently changed the strict `<` comparison to `<=`, introducing the vulnerability. Version 0.1.0-rc.4 fixes the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-01-28 14:53 UTC

CWE

CWE-347 - Improper Verification of Cryptographic Signature

Assigner

GitHub_M mitre root Scorecard

References

11 references

URL	Tags
https://github.com/RustCrypto/signatures/security…	x_refsource_CONFIRM
https://github.com/RustCrypto/signatures/issues/894	x_refsource_MISC
https://github.com/RustCrypto/signatures/pull/895	x_refsource_MISC
https://github.com/RustCrypto/signatures/commit/4…	x_refsource_MISC
https://github.com/RustCrypto/signatures/commit/b…	x_refsource_MISC
https://csrc.nist.gov/pubs/fips/204/final	x_refsource_MISC
https://datatracker.ietf.org/doc/html/rfc9881	x_refsource_MISC
https://github.com/C2SP/wycheproof	x_refsource_MISC
https://github.com/C2SP/wycheproof/blob/master/te…	x_refsource_MISC
https://github.com/C2SP/wycheproof/blob/master/te…	x_refsource_MISC
https://github.com/C2SP/wycheproof/blob/master/te…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
RustCrypto	signatures	Affected: >= 0.0.4, < 0.1.0-rc.4

Show details on NVD website

JSON

To clipboard

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EUVD-2026-266800

European Vulnerability Database identifier assigned by ENISA

Reserved

2026-10-02 07:02

Assigner

ENISA

Alias of

a CVE record, shown under related vulnerabilities. This identifier carries no description, severity or references of its own: they belong to that CVE.

JSON

To clipboard

{
  "assigner": "ENISA",
  "date_reserved": "2026-10-02T07:02:17.272808+00:00",
  "id": "EUVD-2026-266800"
}

FKIE_CVE-2026-24850

Vulnerability from fkie_nvd - Published: 2026-01-28 01:16 - Updated: 2026-06-17 10:23

Severity

5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Summary

References

	URL	Tags
	security-advisories@github.com	https://csrc.nist.gov/pubs/fips/204/final
	security-advisories@github.com	https://datatracker.ietf.org/doc/html/rfc9881
	security-advisories@github.com	https://github.com/C2SP/wycheproof
	security-advisories@github.com	https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_44_verify_test.json
	security-advisories@github.com	https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_65_verify_test.json
	security-advisories@github.com	https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_87_verify_test.json
	security-advisories@github.com	https://github.com/RustCrypto/signatures/commit/400961412be2e2ab787942cf30e0a9b66b37a54a
	security-advisories@github.com	https://github.com/RustCrypto/signatures/commit/b01c3b73dd08d0094e089aa234f78b6089ec1f38
	security-advisories@github.com	https://github.com/RustCrypto/signatures/issues/894
	security-advisories@github.com	https://github.com/RustCrypto/signatures/pull/895
	security-advisories@github.com	https://github.com/RustCrypto/signatures/security/advisories/GHSA-5x2r-hc65-25f9

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "signatures",
          "vendor": "RustCrypto",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 0.0.4, \u003c 0.1.0-rc.4"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The ML-DSA crate is a Rust implementation of the Module-Lattice-Based Digital Signature Standard (ML-DSA). Starting in version 0.0.4 and prior to version 0.1.0-rc.4, the ML-DSA signature verification implementation in the RustCrypto `ml-dsa` crate incorrectly accepts signatures with repeated (duplicate) hint indices. According to the ML-DSA specification (FIPS 204 / RFC 9881), hint indices within each polynomial must be **strictly increasing**. The current implementation uses a non-strict monotonic check (`\u003c=` instead of `\u003c`), allowing duplicate indices. This is a regression bug. The original implementation was correct, but a commit in version 0.0.4 inadvertently changed the strict `\u003c` comparison to `\u003c=`, introducing the vulnerability. Version 0.1.0-rc.4 fixes the issue."
    },
    {
      "lang": "es",
      "value": "El *crate* ML-DSA es una implementaci\u00f3n en Rust del Est\u00e1ndar de Firma Digital Basado en M\u00f3dulos de Ret\u00edculos (ML-DSA). A partir de la versi\u00f3n 0.0.4 y antes de la versi\u00f3n 0.1.0-rc.4, la implementaci\u00f3n de verificaci\u00f3n de firma ML-DSA en el *crate* \u0027ml-dsa\u0027 de RustCrypto acepta incorrectamente firmas con \u00edndices de pista repetidos (duplicados). Seg\u00fan la especificaci\u00f3n ML-DSA (FIPS 204 / RFC 9881), los \u00edndices de pista dentro de cada polinomio deben ser estrictamente crecientes. La implementaci\u00f3n actual utiliza una comprobaci\u00f3n mon\u00f3tona no estricta (\u0027\u0026lt;=\u0027 en lugar de \u0027\u0026lt;\u0027), permitiendo \u00edndices duplicados. Esto es un error de regresi\u00f3n. La implementaci\u00f3n original era correcta, pero un *commit* en la versi\u00f3n 0.0.4 cambi\u00f3 inadvertidamente la comparaci\u00f3n estricta \u0027\u0026lt;\u0027 a \u0027\u0026lt;=\u0027, introduciendo la vulnerabilidad. La versi\u00f3n 0.1.0-rc.4 corrige el problema."
    }
  ],
  "id": "CVE-2026-24850",
  "lastModified": "2026-06-17T10:23:42.150",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-24850",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-01-28T14:53:25.394412Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-01-28T01:16:15.097",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://csrc.nist.gov/pubs/fips/204/final"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://datatracker.ietf.org/doc/html/rfc9881"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/C2SP/wycheproof"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_44_verify_test.json"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_65_verify_test.json"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_87_verify_test.json"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/RustCrypto/signatures/commit/400961412be2e2ab787942cf30e0a9b66b37a54a"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/RustCrypto/signatures/commit/b01c3b73dd08d0094e089aa234f78b6089ec1f38"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/RustCrypto/signatures/issues/894"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/RustCrypto/signatures/pull/895"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/RustCrypto/signatures/security/advisories/GHSA-5x2r-hc65-25f9"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-347"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}

GHSA-5X2R-HC65-25F9

Vulnerability from github – Published: 2026-01-28 16:44 – Updated: 2026-01-28 16:44

Summary

ML-DSA Signature Verification Accepts Signatures with Repeated Hint Indices

Details

Affected Crate: ml-dsa
Affected Versions: v0.1.0-rc.2 (and commits since b01c3b7)
Severity: Medium
Reporter: Oren Yomtov (Fireblocks)

Summary

The ML-DSA signature verification implementation in the RustCrypto ml-dsa crate incorrectly accepts signatures with repeated (duplicate) hint indices. According to the ML-DSA specification (FIPS 204 / RFC 9881), hint indices within each polynomial must be strictly increasing. The current implementation uses a non-strict monotonic check (<= instead of <), allowing duplicate indices.

Note: This is a regression bug. The original implementation was correct, but commit b01c3b7 ("Make ML-DSA signature decoding follow the spec (#895)", fixing issue #894) inadvertently changed the strict < comparison to <=, introducing the vulnerability.

Vulnerability Details

Root Cause

The vulnerability is located in the monotonic helper function in ml-dsa/src/hint.rs:

fn monotonic(a: &[usize]) -> bool {
    a.iter().enumerate().all(|(i, x)| i == 0 || a[i - 1] <= *x)
}

The comparison operator <= allows equal consecutive values, meaning duplicate hint indices are not rejected. The correct implementation should use strict less-than (<):

fn monotonic(a: &[usize]) -> bool {
    a.iter().enumerate().all(|(i, x)| i == 0 || a[i - 1] < *x)
}

Regression Analysis

Original correct code (commit 1d3a1d1 - "Add support for ML-DSA (#877)"): Used < (strict)
Bug introduced (commit b01c3b7 - "Make ML-DSA signature decoding follow the spec (#895)"): Changed to <=

The commit message suggests it was intended to fix issue #894 and make decoding follow the spec, but the change to the monotonic function was in the wrong direction. The other changes in that commit (to use_hint function) may have been correct, but this specific change introduced signature malleability.

Technical Impact

This vulnerability allows signature malleability - the same logical signature can have multiple valid byte-level encodings. An attacker can take a valid signature and create additional "valid" signatures by duplicating hint indices.

Per the ML-DSA specification (FIPS 204, Section 6.2 and Algorithm 26 HintBitUnpack), hint indices must be strictly increasing to ensure a unique, canonical encoding. Accepting non-canonical signatures can lead to:

Signature Malleability: Multiple distinct byte sequences verify as valid for the same message/key pair
Protocol-Level Vulnerabilities: Systems that rely on signature uniqueness (e.g., for transaction deduplication, replay protection, or signature-based identifiers) may be vulnerable
Interoperability Issues: Non-compliant signatures may be rejected by other conforming implementations

Affected Security Levels

All ML-DSA parameter sets are affected: - ML-DSA-44 (NIST Security Level 2) - ML-DSA-65 (NIST Security Level 3) - ML-DSA-87 (NIST Security Level 5)

Proof of Concept

See the file poc_mldsa_repeated_hint.rs for a standalone proof of concept that demonstrates the vulnerability.

The PoC uses test vectors from the Wycheproof test suite that specifically test for this invalid encoding:

Test Vector Source: Wycheproof ML-DSA Test Vectors
Test Case ID 18: "signature with a repeated hint"
Expected Result: invalid
Actual Result: valid (BUG)

Remediation

Update the monotonic function in ml-dsa/src/hint.rs to use strict less-than comparison:

fn monotonic(a: &[usize]) -> bool {
    a.iter().enumerate().all(|(i, x)| i == 0 || a[i - 1] < *x)
}

Design Intent: ML-DSA is NOT Intended to Allow Malleability

While some cryptographic libraries intentionally permit signature malleability for compatibility or performance reasons, ML-DSA is explicitly designed to prevent it:

FIPS 204 Specification: ML-DSA is designed to be strongly unforgeable under chosen message attacks (SUF-CMA). This security property explicitly prevents signature malleability.
NIST PQC Forum Discussion: In February 2024, there was a discussion on the NIST PQC forum about potential malleability in ML-DSA's hint unpacking. The consensus was that ML-DSA is intended to be SUF-CMA, meaning any malleability issues should be considered bugs and fixed.
No Documentation of Intentional Malleability: There is no documentation in the RustCrypto ml-dsa crate, FIPS 204, or RFC 9881 suggesting that signature malleability is an acceptable or intentional property.
Regression Bug: The fact that the original implementation had strict ordering (<) and this was changed to non-strict (<=) in a "fix" commit suggests this was an unintentional regression, not a design decision.

Severity

5.3 (Medium)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "crates.io",
        "name": "ml-dsa"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.0.4"
            },
            {
              "fixed": "0.1.0-rc.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-24850"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-347"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-01-28T16:44:47Z",
    "nvd_published_at": "2026-01-28T01:16:15Z",
    "severity": "MODERATE"
  },
  "details": "**Affected Crate:** `ml-dsa`  \n**Affected Versions:** v0.1.0-rc.2 (and commits since `b01c3b7`)  \n**Severity:** Medium  \n**Reporter:** Oren Yomtov (Fireblocks)\n\n## Summary\n\nThe ML-DSA signature verification implementation in the RustCrypto `ml-dsa` crate incorrectly accepts signatures with repeated (duplicate) hint indices. According to the ML-DSA specification (FIPS 204 / RFC 9881), hint indices within each polynomial must be **strictly increasing**. The current implementation uses a non-strict monotonic check (`\u003c=` instead of `\u003c`), allowing duplicate indices.\n\n**Note:** This is a regression bug. The original implementation was correct, but commit `b01c3b7` (\"Make ML-DSA signature decoding follow the spec (#895)\", fixing issue #894) inadvertently changed the strict `\u003c` comparison to `\u003c=`, introducing the vulnerability.\n\n## Vulnerability Details\n\n### Root Cause\n\nThe vulnerability is located in the `monotonic` helper function in `ml-dsa/src/hint.rs`:\n\n```rust\nfn monotonic(a: \u0026[usize]) -\u003e bool {\n    a.iter().enumerate().all(|(i, x)| i == 0 || a[i - 1] \u003c= *x)\n}\n```\n\nThe comparison operator `\u003c=` allows equal consecutive values, meaning duplicate hint indices are not rejected. The correct implementation should use strict less-than (`\u003c`):\n\n```rust\nfn monotonic(a: \u0026[usize]) -\u003e bool {\n    a.iter().enumerate().all(|(i, x)| i == 0 || a[i - 1] \u003c *x)\n}\n```\n\n### Regression Analysis\n\n- **Original correct code** (commit `1d3a1d1` - \"Add support for ML-DSA (#877)\"): Used `\u003c` (strict)\n- **Bug introduced** (commit `b01c3b7` - \"Make ML-DSA signature decoding follow the spec (#895)\"): Changed to `\u003c=`\n\nThe commit message suggests it was intended to fix issue #894 and make decoding follow the spec, but the change to the `monotonic` function was in the wrong direction. The other changes in that commit (to `use_hint` function) may have been correct, but this specific change introduced signature malleability.\n\n### Technical Impact\n\nThis vulnerability allows **signature malleability** - the same logical signature can have multiple valid byte-level encodings. An attacker can take a valid signature and create additional \"valid\" signatures by duplicating hint indices.\n\nPer the ML-DSA specification (FIPS 204, Section 6.2 and Algorithm 26 `HintBitUnpack`), hint indices must be strictly increasing to ensure a unique, canonical encoding. Accepting non-canonical signatures can lead to:\n\n1. **Signature Malleability:** Multiple distinct byte sequences verify as valid for the same message/key pair\n2. **Protocol-Level Vulnerabilities:** Systems that rely on signature uniqueness (e.g., for transaction deduplication, replay protection, or signature-based identifiers) may be vulnerable\n3. **Interoperability Issues:** Non-compliant signatures may be rejected by other conforming implementations\n\n### Affected Security Levels\n\nAll ML-DSA parameter sets are affected:\n- ML-DSA-44 (NIST Security Level 2)\n- ML-DSA-65 (NIST Security Level 3)\n- ML-DSA-87 (NIST Security Level 5)\n\n## Proof of Concept\n\nSee the file [`poc_mldsa_repeated_hint.rs`](https://gist.github.com/orenyomtov/fb4616eb77d33017f41a71b30aa41a04) for a standalone proof of concept that demonstrates the vulnerability.\n\nThe PoC uses test vectors from the Wycheproof test suite that specifically test for this invalid encoding:\n\n- **Test Vector Source:** [Wycheproof ML-DSA Test Vectors](https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_44_verify_test.json)\n- Test Case ID 18: \"signature with a repeated hint\"\n- Expected Result: `invalid`\n- Actual Result: `valid` (BUG)\n\n## Remediation\n\nUpdate the `monotonic` function in `ml-dsa/src/hint.rs` to use strict less-than comparison:\n\n```rust\nfn monotonic(a: \u0026[usize]) -\u003e bool {\n    a.iter().enumerate().all(|(i, x)| i == 0 || a[i - 1] \u003c *x)\n}\n```\n\n## Design Intent: ML-DSA is NOT Intended to Allow Malleability\n\nWhile some cryptographic libraries intentionally permit signature malleability for compatibility or performance reasons, **ML-DSA is explicitly designed to prevent it**:\n\n1. **FIPS 204 Specification:** ML-DSA is designed to be strongly unforgeable under chosen message attacks (SUF-CMA). This security property explicitly prevents signature malleability.\n\n2. **NIST PQC Forum Discussion:** In February 2024, there was a discussion on the NIST PQC forum about potential malleability in ML-DSA\u0027s hint unpacking. The consensus was that ML-DSA is intended to be SUF-CMA, meaning any malleability issues should be considered bugs and fixed.\n\n3. **No Documentation of Intentional Malleability:** There is no documentation in the RustCrypto `ml-dsa` crate, FIPS 204, or RFC 9881 suggesting that signature malleability is an acceptable or intentional property.\n\n4. **Regression Bug:** The fact that the original implementation had strict ordering (`\u003c`) and this was changed to non-strict (`\u003c=`) in a \"fix\" commit suggests this was an unintentional regression, not a design decision.",
  "id": "GHSA-5x2r-hc65-25f9",
  "modified": "2026-01-28T16:44:47Z",
  "published": "2026-01-28T16:44:47Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/RustCrypto/signatures/security/advisories/GHSA-5x2r-hc65-25f9"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-24850"
    },
    {
      "type": "WEB",
      "url": "https://github.com/RustCrypto/signatures/issues/894"
    },
    {
      "type": "WEB",
      "url": "https://github.com/RustCrypto/signatures/pull/895"
    },
    {
      "type": "WEB",
      "url": "https://github.com/RustCrypto/signatures/commit/400961412be2e2ab787942cf30e0a9b66b37a54a"
    },
    {
      "type": "WEB",
      "url": "https://github.com/RustCrypto/signatures/commit/b01c3b73dd08d0094e089aa234f78b6089ec1f38"
    },
    {
      "type": "WEB",
      "url": "https://csrc.nist.gov/pubs/fips/204/final"
    },
    {
      "type": "WEB",
      "url": "https://datatracker.ietf.org/doc/html/rfc9881"
    },
    {
      "type": "WEB",
      "url": "https://github.com/C2SP/wycheproof"
    },
    {
      "type": "WEB",
      "url": "https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_44_verify_test.json"
    },
    {
      "type": "WEB",
      "url": "https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_65_verify_test.json"
    },
    {
      "type": "WEB",
      "url": "https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_87_verify_test.json"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/RustCrypto/signatures"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "ML-DSA Signature Verification Accepts Signatures with Repeated Hint Indices"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

CVE-2026-24850 (GCVE-0-2026-24850)

EUVD-2026-266800

FKIE_CVE-2026-24850

GHSA-5X2R-HC65-25F9

Summary

Vulnerability Details

Root Cause

Regression Analysis

Technical Impact

Affected Security Levels

Proof of Concept

Remediation

Design Intent: ML-DSA is NOT Intended to Allow Malleability

Tags

Sightings

Nomenclature

Related by attack behaviour