CVE-2026-8956 :: Enginsight Vulnerability Database

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	Primary	9.8 CRITICAL	NETWORK	LOW	NONE	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Base Score

CVSS 3.x

EPSS Score

Percentile: Unknown

Affected Products (NVD)

Vendor	Product	Version
mozilla	firefox_esr	𝑥 < 140.11.0
mozilla	firefox	𝑥 < 151.0.0
mozilla	thunderbird_esr	𝑥 < 140.11
mozilla	thunderbird	𝑥 < 151.0.0

𝑥

= Vulnerable software versions

Debian Releases

Debian Product

Codename

firefox

sid	vulnerable

firefox-esr

bookworm	vulnerable
bookworm (security)	vulnerable
bullseye	vulnerable
bullseye (security)	vulnerable
forky	vulnerable
sid	vulnerable
trixie	vulnerable
trixie (security)	vulnerable

thunderbird

bookworm	vulnerable
bookworm (security)	vulnerable
bullseye	vulnerable
bullseye (security)	vulnerable
forky	vulnerable
sid	vulnerable
trixie	vulnerable
trixie (security)	vulnerable

Common Weakness Enumeration

CWE-190 - Integer Overflow or Wraparound
The software performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control.

Vulnerability Media Exposure

[GERMAN] Mozilla Firefox und Thunderbird: Mehrere Schwachstellen
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Mozilla Firefox, Mozilla Firefox ESR und Mozilla Thunderbird ausnutzen, um beliebigen Code auszuführen, um Informationen offenzulegen, Sicherheitsbeschränkungen zu umgehen (z. B. Sandbox-Escape), den Benutzer zu täuschen, Berechtigungen zu eskalieren oder einen Denial-of-Service-Zustand herbeizuführen.
Published: 2026-05-19T22:00:00+00:00

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/