Cyber Resilience

CVE-2021-29986

HighPublic PoC

Published: 17 August 2021

Published
17 August 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0059 69.6th percentile
Risk Priority 17 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-29986 is a high-severity Race Condition (CWE-362) vulnerability in Mozilla Firefox. Its CVSS base score is 8.1 (High).

Operationally, ranked in the top 30.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

A suspected race condition when calling getaddrinfo led to memory corruption and a potentially exploitable crash. *Note: This issue only affected Linux operating systems. Other operating systems are unaffected.* This vulnerability affects Thunderbird < 78.13, Thunderbird < 91, Firefox ESR…

more

< 78.13, and Firefox < 91.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

mozilla
firefox
≤ 91.0
mozilla
firefox esr
≤ 78.13.0
mozilla
thunderbird
≤ 78.13.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-362

Accurate timestamps from internal clocks enable detection of race conditions by providing reliable event ordering in audit logs.

addresses: CWE-362

Coordination of concurrent security activities reduces the probability that shared resources will be accessed simultaneously without proper synchronization.

References