CVE-2020-15667

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-10-01 · updated 2026-06-17
Weakness: CWE-787

Description

When processing a MAR update file, after the signature has been validated, an invalid name length could result in a heap overflow, leading to memory corruption and potentially arbitrary code execution. Within Firefox as released by Mozilla, this issue is only exploitable with the Mozilla-controlled signing key. This vulnerability affects Firefox < 80.

Affected products

Mozilla Firefox: before 80.0 — fixed in 80.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 80.0. Check the vendor advisory for mitigations.

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1653371
https://www.mozilla.org/security/advisories/mfsa2020-36/
https://bugzilla.mozilla.org/show_bug.cgi?id=1653371
https://www.mozilla.org/security/advisories/mfsa2020-36/

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