CVE-2026-76957 (GCVE-0-2026-76957)

Vulnerability from cvelistv5 – Published: 2026-08-20 04:28 – Updated: 2026-08-20 15:26
VLAI
Summary
libexpat before 2.8.4 lacks handler call depth tracking with custom encoding callbacks. Thus, a use-after-free can occur. NOTE: this is similar to CVE-2026-50219, CVE-2026-56131 and CVE-2026-56412.
Severity
4.9 (Medium)
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-20 15:05 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
libexpat project libexpat Affected: 0 , < 2.8.4 (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

  • 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.


Detection rules are retrieved from Rulezet.