Cyber Resilience

CVE-2021-38495

High

Published: 03 November 2021

Published
03 November 2021
Modified
21 November 2024
KEV Added
—
Patch
—
CVSS Score v3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0054 68.0th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-38495 is a high-severity Out-of-bounds Write (CWE-787) vulnerability in Mozilla Firefox Esr. Its CVSS base score is 8.8 (High).

Operationally, ranked in the top 32.0% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

Mozilla developers reported memory safety bugs present in Thunderbird 78.13.0. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects…

more

Thunderbird < 91.1 and Firefox ESR < 91.1.

CWE(s)
CWE-787

Related Threats

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

Affected Assets

mozilla
firefox esr
≤ 91.1
mozilla
thunderbird
≤ 91.1

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.

SI-16 Memory Protection
addresses: CWE-787

Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.

References