Vulnerability-Lookup

GHSA-2FR4-JFVM-CHMP

Vulnerability from github – Published: 2026-08-21 21:31 – Updated: 2026-08-21 21:31

Details

PDFio before 1.6.5 contains a dangling pointer vulnerability in the dictionary string-formatting function that stores a pointer to a stack-local buffer in the document dictionary without copying the string value. In multi-threaded or pooled-request environments, attackers or concurrent users can trigger stack memory reuse across requests, causing cross-tenant document content corruption by silently overwriting one caller's dictionary string values with another caller's data.

Severity

6.5 (Medium)


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

7.1 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

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{
  "affected": [],
  "aliases": [
    "CVE-2026-77220"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-825"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-21T21:17:06Z",
    "severity": "HIGH"
  },
  "details": "PDFio before 1.6.5 contains a dangling pointer vulnerability in the dictionary string-formatting function that stores a pointer to a stack-local buffer in the document dictionary without copying the string value. In multi-threaded or pooled-request environments, attackers or concurrent users can trigger stack memory reuse across requests, causing cross-tenant document content corruption by silently overwriting one caller\u0027s dictionary string values with another caller\u0027s data.",
  "id": "GHSA-2fr4-jfvm-chmp",
  "modified": "2026-08-21T21:31:52Z",
  "published": "2026-08-21T21:31:52Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-77220"
    },
    {
      "type": "WEB",
      "url": "https://github.com/michaelrsweet/pdfio/commit/22b9afc800c5833f9e851e35938972bd4c76a357"
    },
    {
      "type": "WEB",
      "url": "https://github.com/michaelrsweet/pdfio/releases/tag/v1.6.5"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/pdfio-dangling-pointer-via-dictionary-string-formatting"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-77220 (GCVE-0-2026-77220)

Vulnerability from cvelistv5 – Published: 2026-08-21 20:54 – Updated: 2026-10-01 15:21 X_Open Source

Title

PDFio < 1.6.5 Dangling Pointer via Dictionary String-Formatting

Summary

Severity

7.1 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

6.5 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-24 19:40 UTC

CWE

CWE-825 - Expired Pointer Dereference

Assigner

VulnCheck mitre root Scorecard

References

3 references

URL	Tags
https://github.com/michaelrsweet/pdfio/releases/t…	release-notes
https://github.com/michaelrsweet/pdfio/commit/22b…	patch
https://www.vulncheck.com/advisories/pdfio-dangli…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
michaelrsweet	pdfio	Affected: 0 , < 1.6.5 (semver) cpe:2.3:a:msweet:pdfio::::::::

Date Public

2026-08-19 00:00

Credits

Joshua Rogers (AISLE Research)

Show details on NVD website

JSON

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                "timestamp": "2026-08-24T19:40:29.774950Z",
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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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GHSA-2FR4-JFVM-CHMP

CVE-2026-77220 (GCVE-0-2026-77220)

Tags

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Nomenclature

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