CVE-2026-74735

linux: In the Linux kernel, the following vulnerability has been resolved: l2tp: fix tunnel and session refcount leak on se...

CVE-2026-74735 is fixed in 52 products on 1 platform, first by DEBIAN-CVE-2026-74735, released September 4, 2026. It is not reported as exploited. Patch Radar priority: Routine.

Routine
CVSS
4.4
IMPORTANT
Exploitation
None reported
No vendor assessment
CISA KEV
Not listed
Not in the Known Exploited Vulnerabilities catalog
EPSS
0.0022
12th percentile

In the Linux kernel, the following vulnerability has been resolved: l2tp: fix tunnel and session refcount leak on seq_file release In pppol2tp_proc_open() and l2tp_dfs_seq_open(), iteration state (pd->tunnel and pd->session) is kept in seq_file private data to allow iteration across multiple read() system calls. However, if userspace closes /proc/net/pppol2tp or /sys/kernel/debug/l2tp/tunnels before reading to end-of-file (EOF), any tunnel or session reference stored in pd->tunnel / pd->session is left un-dropped when seq_file private data is freed. Fix this by dropping any remaining pd->tunnel and pd->session references in pppol2tp_proc_release() and l2tp_dfs_seq_release() when closing the file.

Where it's fixed

ProductFixed inFixReleased
Linux
dtb-aarch64 · opensuse-leap 16.0 6.12.0-160000.39.1 OPENSUSE-SU-2026:22091-1 Nov 7, 2026
kernel-64kb · opensuse-leap 16.0 6.12.0-160000.39.1 OPENSUSE-SU-2026:22091-1 Nov 7, 2026
kernel-64kb · sles 15.7 6.4.0-150700.53.84.1 SUSE-SU-2026:4706-1 Nov 7, 2026
kernel-64kb · sles 16.0 6.12.0-160000.39.1 SUSE-SU-2026:24235-1 Nov 7, 2026
kernel-azure · opensuse-leap 16.0 6.12.0-160000.39.1 OPENSUSE-SU-2026:22091-1 Nov 7, 2026
kernel-azure · sles 15.7 6.4.0-150700.53.84.1 SUSE-SU-2026:4706-1 Nov 7, 2026
kernel-azure · sles 16.0 6.12.0-160000.39.1 SUSE-SU-2026:24235-1 Nov 7, 2026
kernel-default · opensuse-leap 16.0 6.12.0-160000.39.1 OPENSUSE-SU-2026:22091-1 Nov 7, 2026
kernel-default · sles 15.7 6.4.0-150700.53.84.1 SUSE-SU-2026:4706-1 Nov 7, 2026
kernel-default · sles 16.0 6.12.0-160000.39.1 SUSE-SU-2026:24197-1 Nov 7, 2026
kernel-default-base · opensuse-leap 16.0 6.12.0-160000.39.1.160000.2.25 OPENSUSE-SU-2026:22091-1 Nov 7, 2026
kernel-default-base · sles 15.7 6.4.0-150700.53.84.1.150700.17.47.1 SUSE-SU-2026:4706-1 Nov 7, 2026
kernel-default-base · sles 16.0 6.12.0-160000.39.1.160000.2.26 SUSE-SU-2026:24235-1 Nov 7, 2026
kernel-docs · opensuse-leap 16.0 6.12.0-160000.39.1 OPENSUSE-SU-2026:22091-1 Nov 7, 2026
kernel-docs · sles 15.7 6.4.0-150700.53.84.1 SUSE-SU-2026:4706-1 Nov 7, 2026
kernel-docs · sles 16.0 6.12.0-160000.39.1 SUSE-SU-2026:24235-1 Nov 7, 2026
kernel-kvmsmall · opensuse-leap 16.0 6.12.0-160000.39.1 OPENSUSE-SU-2026:22091-1 Nov 7, 2026
kernel-kvmsmall · sles 16.0 6.12.0-160000.39.1 SUSE-SU-2026:24235-1 Nov 7, 2026
kernel-livepatch-SLE15-SP7-RT_Update_21 · sles 15.7 1-150700.1.3.1 SUSE-SU-2026:4640-1 Nov 7, 2026
kernel-livepatch-SLE15-SP7_Update_22 · sles 15.7 1-150700.15.3.1 SUSE-SU-2026:4706-1 Nov 7, 2026
kernel-obs-build · opensuse-leap 16.0 6.12.0-160000.39.1 OPENSUSE-SU-2026:22091-1 Nov 7, 2026
kernel-obs-build · sles 15.7 6.4.0-150700.53.84.1 SUSE-SU-2026:4706-1 Nov 7, 2026
kernel-obs-qa · opensuse-leap 16.0 6.12.0-160000.39.1 OPENSUSE-SU-2026:22091-1 Nov 7, 2026
kernel-obs-qa · sles 16.0 6.12.0-160000.39.1 SUSE-SU-2026:24235-1 Nov 7, 2026
kernel-rt · opensuse-leap 16.0 6.12.0-160000.39.1 OPENSUSE-SU-2026:22091-1 Nov 7, 2026
kernel-source · opensuse-leap 16.0 6.12.0-160000.39.1 OPENSUSE-SU-2026:22091-1 Nov 7, 2026
kernel-source · sles 15.7 6.4.0-150700.53.84.1 SUSE-SU-2026:4706-1 Nov 7, 2026
kernel-source · sles 16.0 6.12.0-160000.39.1 SUSE-SU-2026:24235-1 Nov 7, 2026
kernel-syms · opensuse-leap 16.0 6.12.0-160000.39.1 OPENSUSE-SU-2026:22091-1 Nov 7, 2026
kernel-syms · sles 15.7 6.4.0-150700.53.84.1 SUSE-SU-2026:4706-1 Nov 7, 2026
kernel-syms · sles 16.0 6.12.0-160000.39.1 SUSE-SU-2026:24235-1 Nov 7, 2026
kernel-uek · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-core · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-core · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-core · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-core · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-devel · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-devel · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-core · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-core · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-deprecated · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-deprecated · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-desktop · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-desktop · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-extra · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-extra · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-extra-netfilter · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-extra-netfilter · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-usb · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-usb · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-wireless · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-debug-modules-wireless · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-devel · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-devel · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-doc · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-doc · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-core · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-core · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-deprecated · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-deprecated · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-desktop · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-desktop · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-extra · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-extra · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-extra-netfilter · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-extra-netfilter · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-usb · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-usb · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-wireless · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-modules-wireless · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-tools · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek-tools · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-core · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-core · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-devel · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-devel · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-core · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-core · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-deprecated · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-deprecated · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-desktop · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-desktop · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-extra · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-extra · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-extra-netfilter · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-extra-netfilter · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-usb · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-usb · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-wireless · ol 10 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-uek64k-modules-wireless · ol 9 0:6.12.0-207.111.5.1.el9uek ELSA-2026-500374 Oct 7, 2026
kernel-zfcpdump · opensuse-leap 16.0 6.12.0-160000.39.1 OPENSUSE-SU-2026:22091-1 Nov 7, 2026
kernel-zfcpdump · sles 15.7 6.4.0-150700.53.84.1 SUSE-SU-2026:4706-1 Nov 7, 2026
kernel-zfcpdump · sles 16.0 6.12.0-160000.39.1 SUSE-SU-2026:24235-1 Nov 7, 2026
linux · Debian 13.5 (trixie) 6.12.111-1 DEBIAN-CVE-2026-74735 Sep 4, 2026
linux · Debian 14 7.1.10-1 DEBIAN-CVE-2026-74735 Sep 4, 2026
linux-6.12 · Debian 12.15 (bookworm) 6.12.111-1~deb12u1 DEBIAN-CVE-2026-74735 Sep 4, 2026

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