CVE-2026-72321
In the Linux kernel, the following vulnerability has been resolved:
ipv4: igmp: Fix potential memory leaks in igmp_mod_timer() and igmp_stop_timer()
When a timer is deleted and not re-armed in igmp_mod_timer(), or stopped in igmp_stop_timer(), the code currently decrements the reference counter of the multicast list entry @im using refcount_dec(&im->refcnt).
However, both functions can be called from the RCU reader path: - igmp_mod_timer() via igmp_heard_query() -> for_each_pmc_rcu() - igmp_stop_timer() via igmp_rcv() -> igmp_heard_report()
If the group im was concurrently removed from the list by ip_mc_dec_group(), its reference count might have already been decremented to 1.
Leer descripción completaMostrar menos
In this case, timer_delete() succeeds, and refcount_dec() decrements the refcount from 1 to 0. Since refcount_dec() does not free the object when it hits 0 (unlike ip_ma_put()), the im structure is leaked.
Fix this by using ip_ma_put(im) instead of refcount_dec(&im->refcnt), and deferring the put until after the spinlock is released.
CVSS
NVD no ha asignado puntuación CVSS a esta CVE (habitual desde el cambio de política de abril de 2026).
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.21%
- Percentil entre todas las CVEs puntuadas: 10
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-72321",
"cveTags": [],
"metrics": {},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "f60ec3058a85447008b88b762c859d336163acb3",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "95128dc74425ec19ed4f2077ccc651e791ff4b75",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "3546deaa0c30a14c7cdb5dc8f2432cb428f0cd36",
"versionType": "git"
}
],
"programFiles": [
"net/ipv4/igmp.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.12"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.12",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/ipv4/igmp.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-08-15T06:22:05.103",
"references": [
{
"url": "https://git.kernel.org/stable/c/3546deaa0c30a14c7cdb5dc8f2432cb428f0cd36",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/95128dc74425ec19ed4f2077ccc651e791ff4b75",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f60ec3058a85447008b88b762c859d336163acb3",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: igmp: Fix potential memory leaks in igmp_mod_timer() and igmp_stop_timer()\n\nWhen a timer is deleted and not re-armed in igmp_mod_timer(), or stopped\nin igmp_stop_timer(), the code currently decrements the reference counter\nof the multicast list entry @im using refcount_dec(&im->refcnt).\n\nHowever, both functions can be called from the RCU reader path:\n- igmp_mod_timer() via igmp_heard_query() -> for_each_pmc_rcu()\n- igmp_stop_timer() via igmp_rcv() -> igmp_heard_report()\n\nIf the group im was concurrently removed from the list by ip_mc_dec_group(),\nits reference count might have already been decremented to 1.\n\nIn this case, timer_delete() succeeds, and refcount_dec() decrements\nthe refcount from 1 to 0. Since refcount_dec() does not free the object\nwhen it hits 0 (unlike ip_ma_put()), the im structure is leaked.\n\nFix this by using ip_ma_put(im) instead of refcount_dec(&im->refcnt),\nand deferring the put until after the spinlock is released."
}
],
"lastModified": "2026-08-17T06:18:35.587",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}