CVE-2026-8956

critical · 9.8

Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

9.8

CVSS

0.6%

EPSS (exploit prob.)

48th

EPSS percentile

2026-05-19

Published

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weaknesses

CWE-190

Affected products

Vendor	Product	Affected versions
mozilla	firefox	< 140.11.0
mozilla	firefox	< 151.0.0
mozilla	thunderbird	< 140.11
mozilla	thunderbird	< 151.0.0

Check a specific version with /api/v1/cve/match.

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2032427
https://www.mozilla.org/security/advisories/mfsa2026-46/
https://www.mozilla.org/security/advisories/mfsa2026-48/
https://www.mozilla.org/security/advisories/mfsa2026-50/
https://www.mozilla.org/security/advisories/mfsa2026-51/

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-8956