Vulnerability-Lookup

GHSA-4J9M-H44M-2HV8

Vulnerability from github – Published: 2026-07-02 20:32 – Updated: 2026-07-02 20:32

Summary

Steeltoe: OAEP setting silently selects PKCS#1 v1.5 padding

Details

Summary

Configuring encrypt:rsa:algorithm=OAEP does not enable OAEP encryption. Due to an incorrect BouncyCastle transformation string, the OAEP setting selects PKCS#1 v1.5, which is the same algorithm as the DEFAULT setting.

Impact

Operators who configure encrypt:rsa:algorithm=OAEP to obtain CCA2-secure padding receive PKCS#1 v1.5 instead. Currently, Decrypt() is called only against operator-controlled configuration data, so no exploitable path exists, but any future code path that exposes a decryption oracle would be Bleichenbacher-vulnerable despite the OAEP setting.

Migration note

Existing {cipher} values produced under the broken OAEP setting were encrypted with PKCS#1 v1.5. The fix makes OAEP use actual OAEP padding, so those values will fail to decrypt after upgrading. Re-encrypt all affected {cipher} values after upgrading.

Severity

1.9 (Low)


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

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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 4.1.0"
      },
      "package": {
        "ecosystem": "NuGet",
        "name": "Steeltoe.Configuration.Encryption"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.0.0"
            },
            {
              "fixed": "4.2.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-50268"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-256",
      "CWE-327"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-02T20:32:21Z",
    "nvd_published_at": "2026-06-17T23:17:04Z",
    "severity": "LOW"
  },
  "details": "### Summary\n\nConfiguring `encrypt:rsa:algorithm=OAEP` does not enable OAEP encryption. Due to an incorrect BouncyCastle transformation string, the `OAEP` setting selects PKCS#1 v1.5, which is the same algorithm as the `DEFAULT` setting.\n\n### Impact\n\nOperators who configure `encrypt:rsa:algorithm=OAEP` to obtain CCA2-secure padding receive PKCS#1 v1.5 instead. Currently, `Decrypt()` is called only against operator-controlled configuration data, so no exploitable path exists, but any future code path that exposes a decryption oracle would be Bleichenbacher-vulnerable despite the `OAEP` setting.\n\n### Migration note\n\nExisting `{cipher}` values produced under the broken `OAEP` setting were encrypted with PKCS#1 v1.5. The fix makes `OAEP` use actual OAEP padding, so those values will fail to decrypt after upgrading. Re-encrypt all affected `{cipher}` values after upgrading.",
  "id": "GHSA-4j9m-h44m-2hv8",
  "modified": "2026-07-02T20:32:21Z",
  "published": "2026-07-02T20:32:21Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/SteeltoeOSS/security-advisories/security/advisories/GHSA-4j9m-h44m-2hv8"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-50268"
    },
    {
      "type": "WEB",
      "url": "https://github.com/SteeltoeOSS/Steeltoe/commit/6cfee5cccddf8f9a31de69b0ca5ccdd771b73e5b"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/SteeltoeOSS/security-advisories"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Steeltoe: OAEP setting silently selects PKCS#1 v1.5 padding"
}

CVE-2026-50268 (GCVE-0-2026-50268)

Vulnerability from cvelistv5 – Published: 2026-06-17 22:01 – Updated: 2026-06-18 13:53

Title

Steeltoe: OAEP setting silently selects PKCS#1 v1.5 padding

Summary

Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. In Steeltoe.Configuration.Encryption 4.0.0 through 4.1.0, configuring `encrypt:rsa:algorithm=OAEP` does not enable OAEP encryption. Due to an incorrect BouncyCastle transformation string, the `OAEP` setting selects PKCS#1 v1.5, which is the same algorithm as the `DEFAULT` setting. Steeltoe.Configuration.Encryption version 4.2.0 patches the issue.

Severity

1.9 (Low)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-18 13:46 UTC

CWE

CWE-256 - Plaintext Storage of a Password
CWE-327 - Use of a Broken or Risky Cryptographic Algorithm

Assigner

GitHub_M mitre root Scorecard

References

2 references

URL	Tags
https://github.com/SteeltoeOSS/security-advisorie…	x_refsource_CONFIRM
https://github.com/SteeltoeOSS/Steeltoe/commit/6c…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
SteeltoeOSS	Steeltoe.Configuration.Encryption	Affected: >= 4.0.0, < 4.2.0

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JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-50268",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-18T13:46:22.767424Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-18T13:53:58.470Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "Steeltoe.Configuration.Encryption",
          "vendor": "SteeltoeOSS",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 4.0.0, \u003c 4.2.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. In Steeltoe.Configuration.Encryption 4.0.0 through 4.1.0, configuring `encrypt:rsa:algorithm=OAEP` does not enable OAEP encryption. Due to an incorrect BouncyCastle transformation string, the `OAEP` setting selects PKCS#1 v1.5, which is the same algorithm as the `DEFAULT` setting. Steeltoe.Configuration.Encryption version 4.2.0 patches the issue."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "NONE",
            "baseScore": 1.9,
            "baseSeverity": "LOW",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "HIGH",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-256",
              "description": "CWE-256: Plaintext Storage of a Password",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-327",
              "description": "CWE-327: Use of a Broken or Risky Cryptographic Algorithm",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-17T22:01:19.712Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/SteeltoeOSS/security-advisories/security/advisories/GHSA-4j9m-h44m-2hv8",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/SteeltoeOSS/security-advisories/security/advisories/GHSA-4j9m-h44m-2hv8"
        },
        {
          "name": "https://github.com/SteeltoeOSS/Steeltoe/commit/6cfee5cccddf8f9a31de69b0ca5ccdd771b73e5b",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/SteeltoeOSS/Steeltoe/commit/6cfee5cccddf8f9a31de69b0ca5ccdd771b73e5b"
        }
      ],
      "source": {
        "advisory": "GHSA-4j9m-h44m-2hv8",
        "discovery": "UNKNOWN"
      },
      "title": "Steeltoe: OAEP setting silently selects PKCS#1 v1.5 padding"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-50268",
    "datePublished": "2026-06-17T22:01:19.712Z",
    "dateReserved": "2026-06-04T16:26:05.984Z",
    "dateUpdated": "2026-06-18T13:53:58.470Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

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Action not permitted

GHSA-4J9M-H44M-2HV8

Summary

Impact

Migration note

CVE-2026-50268 (GCVE-0-2026-50268)

Tags

Sightings

Nomenclature

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