What’s Vulnerable › Vulnerabilities

CVE-2022-26387

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.7% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2022-12-22 · updated 2026-06-17
• Weakness: CWE-367

Description

When installing an add-on, Firefox verified the signature before prompting the user; but while the user was confirming the prompt, the underlying add-on file could have been modified and Firefox would not have noticed. This vulnerability affects Firefox < 98, Firefox ESR < 91.7, and Thunderbird < 91.7.

Affected products

• Mozilla Firefox: before 98.0 — fixed in 98.0
• Mozilla Firefox ESR: before 91.7 — fixed in 91.7
• Mozilla Thunderbird: before 91.7 — fixed in 91.7

How to fix

Upgrade to a fixed version: Mozilla Firefox 98.0; Mozilla Firefox ESR 91.7; Mozilla Thunderbird 91.7. Check the vendor advisory for mitigations.

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=1752979
• https://www.mozilla.org/security/advisories/mfsa2022-10/
• https://www.mozilla.org/security/advisories/mfsa2022-11/
• https://www.mozilla.org/security/advisories/mfsa2022-12/
• https://bugzilla.mozilla.org/show_bug.cgi?id=1752979
• https://www.mozilla.org/security/advisories/mfsa2022-10/
• https://www.mozilla.org/security/advisories/mfsa2022-11/
• https://www.mozilla.org/security/advisories/mfsa2022-12/

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