CVE-2026-56131 (GCVE-0-2026-56131)
Vulnerability from cvelistv5 – Published: 2026-06-19 02:56 – Updated: 2026-06-22 14:58
VLAI
EPSS
VEX
Summary
libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_ResumeParser from within handlers in cases of a policy violation. Thus, a use-after-free can occur (similar to the CVE-2026-50219 situation).
Severity
4.9 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-22 14:58 UTC
CWE
- CWE-416 - Use After Free
Assigner
References
1 reference
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| libexpat project | libexpat |
Affected:
0 , < 2.8.2
(semver)
cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:* |
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| 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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