CVE-2026-113867
Stanza injection in XMPP chat
Description
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.
INFO
Published Date :
Oct. 20, 2026, 8:17 p.m.
Last Modified :
Oct. 20, 2026, 8:17 p.m.
Remotely Exploit :
No
Source :
[email protected]
Solution
- Update Thunderbird to version 158.0.1 or later.
- Disable the chat feature if updates are not possible.
- Avoid connecting to untrusted XMPP servers.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-113867.
| URL | Resource |
|---|---|
| https://bugzilla.mozilla.org/show_bug.cgi?id=2080073 | |
| https://www.mozilla.org/security/advisories/mfsa2026-114/ | |
| https://www.mozilla.org/security/advisories/mfsa2026-115/ |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-113867 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-113867
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-113867 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-113867 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
Oct. 20, 2026
Action Type Old Value New Value Added Description 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. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/113xxx/CVE-2026-113867.json">CVE-2026-113867</a> Added Reference https://bugzilla.mozilla.org/show_bug.cgi?id=2080073 Added Reference https://www.mozilla.org/security/advisories/mfsa2026-114/ Added Reference https://www.mozilla.org/security/advisories/mfsa2026-115/