Vulnerability in Libexpat_project Libexpat

CVE-2021-45960

In Expat (aka libexpat) before 2.4.3, a left shift by 29 (or more) places in the storeAtts function in xmlparse.c can lead to realloc misbehavior (e.g., allocating too few bytes, or only freeing memory).

EPSS: 0.042 (89.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

  • cve@mitre.org (Exploit, Patch, Third Party Advisory, x_refsource_MISC, Issue Tracking)
  • cve@mitre.org (Patch, Third Party Advisory, x_refsource_MISC)
  • cve@mitre.org (Permissions Required, Third Party Advisory, x_refsource_MISC, Issue Tracking)
  • cve@mitre.org (mailing-list, x_refsource_MLIST, Exploit, Mailing List, Third Party Advisory)
  • cve@mitre.org (x_refsource_CONFIRM, Third Party Advisory)
  • cve@mitre.org (x_refsource_CONFIRM, Third Party Advisory)
  • cve@mitre.org (vendor-advisory, Third Party Advisory, Issue Tracking, x_refsource_DEBIAN)
  • cve@mitre.org (x_refsource_CONFIRM, Patch, Third Party Advisory)
  • cve@mitre.org (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)

Frequently asked questions

What is CVE-2021-45960?
CVE-2021-45960 is a high-severity vulnerability in Libexpat_project Libexpat, classified under Incorrect Calculation. CVSS score: 8.8/10. Published 2022-01-01.
How severe is CVE-2021-45960?
High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2021-45960 known to be exploited?
12 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.