CVE-2026-98099
In the Linux kernel, the following vulnerability has been resolved:
ipv6: mcast: use rcu_assign_pointer() for __rcu list updates
Several places in net/ipv6/mcast.c update RCU-protected lists (np->ipv6_mc_list, idev->mc_list, idev->mc_tomb) using direct pointer assignments instead of rcu_assign_pointer():
Fix these by consistently using rcu_assign_pointer() along with mc_dereference() / sock_dereference().
Detalles técnicos trazas, registros y código del informe original
1. In __ipv6_dev_mc_dec(), unlinking a group from idev->mc_list did:
*map = ma->next;
without rcu_assign_pointer() while concurrent readers traverse
idev->mc_list locklessly under rcu_read_lock().
2. In ipv6_sock_mc_drop() and __ipv6_sock_mc_close(), unlinking a group
from np->ipv6_mc_list directly assigned *lnk = mc_lst->next and
np->ipv6_mc_list = mc_lst->next without rcu_assign_pointer(), racing
with lockless readers in inet6_mc_check().
3. In __ipv6_sock_mc_join(), mc_lst->next was initialized to
np->ipv6_mc_list via raw assignment before publishing mc_lst.
4. In mld_del_delrec() and __ipv6_dev_mc_inc(), __rcu source pointers
passed into rcu_assign_pointer() lacked explicit dereference helpers.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: 0.17%
- Percentil entre todas las CVEs puntuadas: 6
- Fecha de la puntuación: 5/10/2026
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-2026-98099",
"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": "456b61bca8ee324ab6c18b065e632c9a8c88aa39",
"lessThan": "2e46b0c9fcf7e10b64ce1630b925f47918d1f7f6",
"versionType": "git"
},
{
"status": "affected",
"version": "456b61bca8ee324ab6c18b065e632c9a8c88aa39",
"lessThan": "0c8f56c583c3250408367880c98e4d6fbc929315",
"versionType": "git"
}
],
"programFiles": [
"net/ipv6/mcast.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.38"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.38",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "7.2.7",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3-rc2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/ipv6/mcast.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-09-25T11:17:39.723",
"references": [
{
"url": "https://git.kernel.org/stable/c/0c8f56c583c3250408367880c98e4d6fbc929315",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/2e46b0c9fcf7e10b64ce1630b925f47918d1f7f6",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Undergoing Analysis",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: mcast: use rcu_assign_pointer() for __rcu list updates\n\nSeveral places in net/ipv6/mcast.c update RCU-protected lists\n(np->ipv6_mc_list, idev->mc_list, idev->mc_tomb) using direct pointer\nassignments instead of rcu_assign_pointer():\n\n1. In __ipv6_dev_mc_dec(), unlinking a group from idev->mc_list did:\n *map = ma->next;\n without rcu_assign_pointer() while concurrent readers traverse\n idev->mc_list locklessly under rcu_read_lock().\n2. In ipv6_sock_mc_drop() and __ipv6_sock_mc_close(), unlinking a group\n from np->ipv6_mc_list directly assigned *lnk = mc_lst->next and\n np->ipv6_mc_list = mc_lst->next without rcu_assign_pointer(), racing\n with lockless readers in inet6_mc_check().\n3. In __ipv6_sock_mc_join(), mc_lst->next was initialized to\n np->ipv6_mc_list via raw assignment before publishing mc_lst.\n4. In mld_del_delrec() and __ipv6_dev_mc_inc(), __rcu source pointers\n passed into rcu_assign_pointer() lacked explicit dereference helpers.\n\nFix these by consistently using rcu_assign_pointer() along with\nmc_dereference() / sock_dereference()."
}
],
"lastModified": "2026-09-30T14:10:59.253",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}