{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-31422","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-03-09T15:48:24.088Z","datePublished":"2026-04-13T13:40:25.911Z","dateUpdated":"2026-05-11T22:08:24.111Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T22:08:24.111Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: cls_flow: fix NULL pointer dereference on shared blocks\n\nflow_change() calls tcf_block_q() and dereferences q->handle to derive\na default baseclass.  Shared blocks leave block->q NULL, causing a NULL\nderef when a flow filter without a fully qualified baseclass is created\non a shared block.\n\nCheck tcf_block_shared() before accessing block->q and return -EINVAL\nfor shared blocks.  This avoids the null-deref shown below:\n\n=======================================================================\nKASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]\nRIP: 0010:flow_change (net/sched/cls_flow.c:508)\nCall Trace:\n tc_new_tfilter (net/sched/cls_api.c:2432)\n rtnetlink_rcv_msg (net/core/rtnetlink.c:6980)\n [...]\n======================================================================="}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/cls_flow.c"],"versions":[{"version":"1abf272022cf1d18469405f47b4ec49c6a3125db","lessThan":"57f94ac7e953eece5ed4819605a18f3cdfc63dcc","status":"affected","versionType":"git"},{"version":"1abf272022cf1d18469405f47b4ec49c6a3125db","lessThan":"942813276edeb1741fa5b0a73471beb4e495fa08","status":"affected","versionType":"git"},{"version":"1abf272022cf1d18469405f47b4ec49c6a3125db","lessThan":"cc707a4fd4c3b6ab2722e06bc359aa010e13d408","status":"affected","versionType":"git"},{"version":"1abf272022cf1d18469405f47b4ec49c6a3125db","lessThan":"4a09f72007201c9f667dc47f64517ec23eea65e5","status":"affected","versionType":"git"},{"version":"1abf272022cf1d18469405f47b4ec49c6a3125db","lessThan":"9bf5fc36a43f7b8b5507c96e74fb81f1e8b4957e","status":"affected","versionType":"git"},{"version":"1abf272022cf1d18469405f47b4ec49c6a3125db","lessThan":"a208c3e1232997e9317887294c20008dfcb75449","status":"affected","versionType":"git"},{"version":"1abf272022cf1d18469405f47b4ec49c6a3125db","lessThan":"415ea0c973c754b9f375225807810eb9045f4293","status":"affected","versionType":"git"},{"version":"1abf272022cf1d18469405f47b4ec49c6a3125db","lessThan":"1a280dd4bd1d616a01d6ffe0de284c907b555504","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/cls_flow.c"],"versions":[{"version":"4.15","status":"affected"},{"version":"0","lessThan":"4.15","status":"unaffected","versionType":"semver"},{"version":"5.10.253","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.203","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.168","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.134","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.81","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.22","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"6.19.12","lessThanOrEqual":"6.19.*","status":"unaffected","versionType":"semver"},{"version":"7.0","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":"4.15","versionEndExcluding":"5.10.253"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"5.15.203"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.1.168"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.6.134"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.12.81"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.18.22"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.19.12"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"7.0"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/57f94ac7e953eece5ed4819605a18f3cdfc63dcc"},{"url":"https://git.kernel.org/stable/c/942813276edeb1741fa5b0a73471beb4e495fa08"},{"url":"https://git.kernel.org/stable/c/cc707a4fd4c3b6ab2722e06bc359aa010e13d408"},{"url":"https://git.kernel.org/stable/c/4a09f72007201c9f667dc47f64517ec23eea65e5"},{"url":"https://git.kernel.org/stable/c/9bf5fc36a43f7b8b5507c96e74fb81f1e8b4957e"},{"url":"https://git.kernel.org/stable/c/a208c3e1232997e9317887294c20008dfcb75449"},{"url":"https://git.kernel.org/stable/c/415ea0c973c754b9f375225807810eb9045f4293"},{"url":"https://git.kernel.org/stable/c/1a280dd4bd1d616a01d6ffe0de284c907b555504"}],"title":"net/sched: cls_flow: fix NULL pointer dereference on shared blocks","x_generator":{"engine":"bippy-1.2.0"}}}}