CVE-2026-76957
CVE-2026-76957 is a medium-severity vulnerability in Libexpat Project Libexpat with a CVSS 3.x base score of 4.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-416.
Key facts
- Severity: Medium (CVSS 3.x base score 4.9)
- EPSS exploit prediction: 0% (1st percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-416
- Affected product: Libexpat Project Libexpat
- Published:
- Last modified:
Description
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.
Frequently asked questions
- What is CVE-2026-76957?
- 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.
- How severe is CVE-2026-76957?
- CVE-2026-76957 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over local access with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
- Is CVE-2026-76957 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-76957?
- CVE-2026-76957 affects Libexpat Project Libexpat. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-76957?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2026-76957 published?
- CVE-2026-76957 was published on 2026-08-20 and last updated on 2026-09-08.
References
Affected products (1)
- cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*
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