Vulnerability in Mozilla Firefox

CVE-2022-26387

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.

Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)

EPSS: 0.007 (47.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2022-26387?
CVE-2022-26387 is a high-severity vulnerability in Mozilla Firefox, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 7.5/10. Published 2022-12-22.
How severe is CVE-2022-26387?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2022-26387 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.