CVE-2026-113867
Full vulnerability record from the local CVENow database.
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.
Severity
CRITICAL
CVSS score
9.1
(v3.1)
Vulnerability status
Awaiting Analysis
Source identifier
Published
2026-10-20 20:17:19.570000
Last modified
2026-10-29 19:17:16.327000
View original CVE JSON
{
"id": "CVE-2026-113867",
"sourceIdentifier": "[email protected]",
"published": "2026-10-20T20:17:19.570",
"lastModified": "2026-10-29T19:17:16.327",
"vulnStatus": "Awaiting Analysis",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "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."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "Mozilla",
"product": "Thunderbird",
"versions": [
{
"version": "153.5.1",
"lessThanOrEqual": "153.*",
"versionType": "rpm",
"status": "unaffected"
},
{
"version": "158.0.1",
"lessThanOrEqual": "*",
"versionType": "rpm",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
"baseScore": 9.1,
"baseSeverity": "CRITICAL",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "NONE"
},
"exploitabilityScore": 3.9,
"impactScore": 5.2
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-10-29T18:27:38.321543Z",
"id": "CVE-2026-113867",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-116"
}
]
}
],
"references": [
{
"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2080073",
"source": "[email protected]"
},
{
"url": "https://www.mozilla.org/security/advisories/mfsa2026-114/",
"source": "[email protected]"
},
{
"url": "https://www.mozilla.org/security/advisories/mfsa2026-115/",
"source": "[email protected]"
}
]
}