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Case File

CVE-2021-43539

HIGH · CVSS 8.8 EPSS 1.62% Public Exploit

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2021-12-08 · Last synced 2026-08-04

CyberRota Analysis

This is a high severity vulnerability with a CVSS score of 8.8. It affects Firefox. Public exploit code or proof-of-concept references have been detected in its references.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

Detected Signals
exploit

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2021-43539
Severity
HIGH
CVSS
8.8
EPSS
1.62%
Firefox

Original NVD Description

Failure to correctly record the location of live pointers across wasm instance calls resulted in a GC occurring within the call not tracing those live pointers. This could have led to a use-after-free causing a potentially exploitable crash. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

Related CVEs

Other vulnerabilities affecting the same vendor(s)