CVE-2026-113868
mediumpriority · track · 0EPSS 0.004 · 37 %ileDEFREPSS · scored 2026-10-27
When authenticating to a POP3 or SMTP server using NTLM, Thunderbird did not check whether the server's challenge was valid base64. A malicious server could send a challenge that caused Thunderbird to include uninitialized heap memory in its NTLM response, disclosing that memory to the server. A challenge consisting only of base64 padding also caused an out-of-bounds read, crashing Thunderbird. This affected accounts configured to use NTLM or GSSAPI authentication. The uninitialized memory disclosure only affected NTLM. This vulnerability was fixed in Thunderbird 158.0.1 and Thunderbird 153.5.1.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (11)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-4064Mozilla Produkte (Thunderbird, Firefox ESR und Firefox): Mehrere SchwachstellenDeutsch2026-10-20csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Mozilla Thunderbird, Mozilla Firefox ESR und Mozilla Firefox ausnutzen, um Sicherheitsvorkehrungen zu umgehen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen und um Daten zu manipulieren.
- CERTFR-2026-AVI-1346Multiples vulnérabilités dans les produits MozillaFrançais2026-10-21vendor · certfrFR
sources
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references (3) nvd
External citations — patches, advisories, analysis.
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