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
VLAI
EPSS
VEX
Title
PDFio < 1.6.5 Dangling Pointer via Dictionary String-Formatting
Summary
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
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
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 | CPE status | |
|---|---|---|---|---|
| michaelrsweet | pdfio |
Affected:
0 , < 1.6.5
(semver)
cpe:2.3:a:msweet:pdfio:*:*:*:*:*:*:*:* |
Date Public
2026-08-19 00:00
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| Author | Source | Type | Date | Other |
|---|
Nomenclature
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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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