CVE-2025-21768
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: net: ipv6: fix dst ref loops in rpl, seg6 and ioam6 lwtunnels Some lwtunnels have a dst cache for post-transformation dst. If the packet destination did not change we may end up recording a reference to the lwtunnel in its own cache, and the lwtunnel state will never be freed. Discovered by the ioam6.sh test, kmemleak was recently fixed to catch per-cpu memory leaks. I'm not sure if rpl and seg6 can actually hit this, but in principle I don't see why not.
Severity
MEDIUM
CVSS score
5.5
(v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2025-02-27 03:15:17.480000
Last modified
2026-10-30 13:17:52.553000
View original CVE JSON
{
"id": "CVE-2025-21768",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2025-02-27T03:15:17.480",
"lastModified": "2026-10-30T13:17:52.553",
"vulnStatus": "Modified",
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"descriptions": [
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"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ipv6: fix dst ref loops in rpl, seg6 and ioam6 lwtunnels\n\nSome lwtunnels have a dst cache for post-transformation dst.\nIf the packet destination did not change we may end up recording\na reference to the lwtunnel in its own cache, and the lwtunnel\nstate will never be freed.\n\nDiscovered by the ioam6.sh test, kmemleak was recently fixed\nto catch per-cpu memory leaks. I'm not sure if rpl and seg6\ncan actually hit this, but in principle I don't see why not."
},
{
"lang": "es",
"value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net: ipv6: arreglo de bucles de referencia dst en lwtunnels rpl, seg6 y ioam6 Algunos lwtunnels tienen una caché dst para dst posterior a la transformación. Si el destino del paquete no cambió, podemos terminar registrando una referencia al lwtunnel en su propia caché, y el estado del lwtunnel nunca se liberará. Descubierto por la prueba ioam6.sh, kmemleak se corrigió recientemente para detectar fugas de memoria por CPU. No estoy seguro de si rpl y seg6 realmente pueden alcanzar esto, pero en principio no veo por qué no."
}
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