CVE-2026-113867
highpriority · track · 0EPSS 0.002 · 7 %ileDEFREPSS · scored 2026-10-27
Thunderbird did not escape attribute values when serializing outgoing XMPP stanzas. Because values from incoming requests were echoed back in automatic replies, a remote XMPP user could send a crafted request that caused Thunderbird to inject arbitrary stanzas into the user's connection, which the server would then process as if sent by the user. This could be used to send messages or change contact and subscription settings on behalf of the user, without any interaction. This bug only affects Thunderbird's chat feature with XMPP accounts. 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
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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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