{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-74735","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-08-15T05:44:03.930Z","datePublished":"2026-08-26T14:36:49.352Z","dateUpdated":"2026-09-21T13:14:07.716Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-21T13:14:07.716Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nl2tp: fix tunnel and session refcount leak on seq_file release\n\nIn pppol2tp_proc_open() and l2tp_dfs_seq_open(), iteration state\n(pd->tunnel and pd->session) is kept in seq_file private data to allow\niteration across multiple read() system calls.\n\nHowever, if userspace closes /proc/net/pppol2tp or /sys/kernel/debug/l2tp/tunnels\nbefore reading to end-of-file (EOF), any tunnel or session reference stored in\npd->tunnel / pd->session is left un-dropped when seq_file private data is freed.\n\nFix this by dropping any remaining pd->tunnel and pd->session references in\npppol2tp_proc_release() and l2tp_dfs_seq_release() when closing the file."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/l2tp/l2tp_debugfs.c","net/l2tp/l2tp_ppp.c"],"versions":[{"version":"0e0c3fee3a59a387aeecc4fca6f3a2e9615a5443","lessThan":"bdf83613781956cc39798ed08321f74ab0467f4d","status":"affected","versionType":"git"},{"version":"0e0c3fee3a59a387aeecc4fca6f3a2e9615a5443","lessThan":"8c4fde01bcf91f22b9c7ded8c3e14addd7ddd500","status":"affected","versionType":"git"},{"version":"0e0c3fee3a59a387aeecc4fca6f3a2e9615a5443","lessThan":"ebe2774e956482dd3c70b8991f6f7654356339e6","status":"affected","versionType":"git"},{"version":"0e0c3fee3a59a387aeecc4fca6f3a2e9615a5443","lessThan":"9006c116dd111d457bf5d074990210f70a4ad2c8","status":"affected","versionType":"git"},{"version":"f6104e9ae04462523c372928b1173766a771ef95","status":"affected","versionType":"git"},{"version":"7f8e401f9e612df2a95c1ef76217c00181389bb5","status":"affected","versionType":"git"},{"version":"c712ed63e9b33d9a282fbd92ce25c64918c3129f","status":"affected","versionType":"git"},{"version":"9a8863e8a8def9d88583cd9c60db38a008e6b8cf","status":"affected","versionType":"git"},{"version":"3.16.60","lessThan":"3.17","status":"affected","versionType":"semver"},{"version":"4.16.6","lessThan":"4.17","status":"affected","versionType":"semver"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/l2tp/l2tp_debugfs.c","net/l2tp/l2tp_ppp.c"],"versions":[{"version":"4.17","status":"affected"},{"version":"0","lessThan":"4.17","status":"unaffected","versionType":"semver"},{"version":"6.12.111","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.53","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.1.10","lessThanOrEqual":"7.1.*","status":"unaffected","versionType":"semver"},{"version":"7.2","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"6.12.111"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"6.18.53"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"7.1.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"7.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16.60"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.16.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16.60"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.16.6"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/bdf83613781956cc39798ed08321f74ab0467f4d"},{"url":"https://git.kernel.org/stable/c/8c4fde01bcf91f22b9c7ded8c3e14addd7ddd500"},{"url":"https://git.kernel.org/stable/c/ebe2774e956482dd3c70b8991f6f7654356339e6"},{"url":"https://git.kernel.org/stable/c/9006c116dd111d457bf5d074990210f70a4ad2c8"}],"title":"l2tp: fix tunnel and session refcount leak on seq_file release","x_generator":{"engine":"bippy-1.2.0"}}}}