CVE-2025-39764
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: remove refcounting in expectation dumpers Same pattern as previous patch: do not keep the expectation object alive via refcount, only store a cookie value and then use that as the skip hint for dump resumption. AFAICS this has the same issue as the one resolved in the conntrack dumper, when we do if (!refcount_inc_not_zero(&exp->use)) to increment the refcount, there is a chance that exp == last, which causes a double-increment of the refcount and subsequent memory leak.
Severity
MEDIUM
CVSS score
5.5
(v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2025-09-11 17:15:40.653000
Last modified
2026-10-19 21:10:00.160000
View original CVE JSON
{
"id": "CVE-2025-39764",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2025-09-11T17:15:40.653",
"lastModified": "2026-10-19T21:10:00.160",
"vulnStatus": "Modified",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ctnetlink: remove refcounting in expectation dumpers\n\nSame pattern as previous patch: do not keep the expectation object\nalive via refcount, only store a cookie value and then use that\nas the skip hint for dump resumption.\n\nAFAICS this has the same issue as the one resolved in the conntrack\ndumper, when we do\n if (!refcount_inc_not_zero(&exp->use))\n\nto increment the refcount, there is a chance that exp == last, which\ncauses a double-increment of the refcount and subsequent memory leak."
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnetfilter: ctnetlink: eliminar el conteo de referencias en los volcadores de expectativas\n\nMismo patrón que el parche anterior: no mantener el objeto de expectativa vivo mediante el conteo de referencias, solo almacenar un valor de cookie y luego usar eso como la pista de omisión para la reanudación del volcado.\n\nPor lo que puedo ver, esto tiene el mismo problema que el resuelto en el volcador de conntrack, cuando hacemos\nif (!refcount_inc_not_zero(&exp->use))\n\npara incrementar el conteo de referencias, existe la posibilidad de que exp == last, lo que causa un doble incremento del conteo de referencias y una fuga de memoria posterior."
}
],
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