CVE-2026-31680

Katalog CVE

CVSS 7.8 · High EPSS 0,18%

Kerentanan pada linux kernel. Skor CVSS 3.1 7.8 (High) menurut CNA.

Deskripsi (NVD)

In the Linux kernel, the following vulnerability has been resolved: net: ipv6: flowlabel: defer exclusive option free until RCU teardown `ip6fl_seq_show()` walks the global flowlabel hash under the seq-file RCU read-side lock and prints `fl->opt->opt_nflen` when an option block is present. Exclusive flowlabels currently free `fl->opt` as soon as `fl->users` drops to zero in `fl_release()`. However, the surrounding `struct ip6_flowlabel` remains visible in the global hash table until later garbage collection removes it and `fl_free_rcu()` finally tears it down. A concurrent `/proc/net/ip6_flowlabel` reader can therefore race that early `kfree()` and dereference freed option state, triggering a crash in `ip6fl_seq_show()`. Fix this by keeping `fl->opt` alive until `fl_free_rcu()`. That matches the lifetime already required for the enclosing flowlabel while readers can still reach it under RCU.

Rincian

Terbit di NVD

25 April 2026

Terakhir diubah

14 Juli 2026

Status NVD

Modified

CVSS 3.1

7.8 (High), sumber CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H · uraikan di kalkulator

EPSS (30 hari)

0,18% peluang dieksploitasi; lebih tinggi dari 7,3% CVE lain

Produk dan versi terdampak

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

• https://git.kernel.org/stable/c/3c54b66c83fb8fcbde8e6a7bf90b65856e39f827 patch
• https://git.kernel.org/stable/c/414726b69921fe6355ae453f5b35e68dd078342a patch
• https://git.kernel.org/stable/c/4b6798024f7b2d535f3db1002c760143cdbd1bd3 patch
• https://git.kernel.org/stable/c/572ce62778519a7d4d1c15f55dd2e45a474133c4 patch
• https://git.kernel.org/stable/c/5a6b15f861b7c1304949e3350d23490a5fe429fd patch
• https://git.kernel.org/stable/c/6c7fbdb8ffde6413640de7cfbd7c976c353e89f8 patch
• https://git.kernel.org/stable/c/8027964931785cb73d520ac70a342a3dc16c249b patch
• https://git.kernel.org/stable/c/9ca562bb8e66978b53028fa32b1a190708e6a091 patch
• https://cert-portal.siemens.com/productcert/html/ssa-019113.html
• https://cert-portal.siemens.com/productcert/html/ssa-082556.html