{"id":"CVE-2026-23433","state":"PUBLISHED","title":"arm_mpam: Fix null pointer dereference when restoring bandwidth counters","description":"In the Linux kernel, the following vulnerability has been resolved:\n\narm_mpam: Fix null pointer dereference when restoring bandwidth counters\n\nWhen an MSC supporting memory bandwidth monitoring is brought offline and\nthen online, mpam_restore_mbwu_state() calls __ris_msmon_read() via ipi to\nrestore the configuration of the bandwidth counters. It doesn't care about\nthe value read, mbwu_arg.val, and doesn't set it leading to a null pointer\ndereference when __ris_msmon_read() adds to it. This results in a kernel\noops with a call trace such as:\n\nCall trace:\n__ris_msmon_read+0x19c/0x64c (P)\nmpam_restore_mbwu_state+0xa0/0xe8\nsmp_call_on_cpu_callback+0x1c/0x38\nprocess_one_work+0x154/0x4b4\nworker_thread+0x188/0x310\nkthread+0x11c/0x130\nret_from_fork+0x10/0x20\n\nProvide a local variable for val to avoid __ris_msmon_read() dereferencing\na null pointer when adding to val.","publishedAt":"2026-04-03T15:15:18.757Z","updatedAt":"2026-05-11T22:06:48.863Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"41e8a14950e1732af51cfec8fa09f8ded02a5ca9","status":"affected","lessThan":"ac3e12bc195786d3d44d730b5b2259fd36191848","versionType":"git"},{"version":"41e8a14950e1732af51cfec8fa09f8ded02a5ca9","status":"affected","lessThan":"4ad79c874e53ebb7fe3b8ae7ac6c858a2121f415","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/resctrl/mpam_devices.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.19","versionType":"semver"},{"version":"6.19.10","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/resctrl/mpam_devices.c"]}],"references":["https://git.kernel.org/stable/c/ac3e12bc195786d3d44d730b5b2259fd36191848","https://git.kernel.org/stable/c/4ad79c874e53ebb7fe3b8ae7ac6c858a2121f415"],"weaknesses":[],"ingestedAt":"2026-10-29T20:11:21.040Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/23xxx/CVE-2026-23433.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-23433","state":"PUBLISHED","datePublished":"2026-04-03T15:15:18.757Z","dateUpdated":"2026-05-11T22:06:48.863Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-01-13T15:37:46.016Z"},"containers":{"cna":{"title":"arm_mpam: Fix null pointer dereference when restoring bandwidth counters","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\narm_mpam: Fix null pointer dereference when restoring bandwidth counters\n\nWhen an MSC supporting memory bandwidth monitoring is brought offline and\nthen online, mpam_restore_mbwu_state() calls __ris_msmon_read() via ipi to\nrestore the configuration of the bandwidth counters. It doesn't care about\nthe value read, mbwu_arg.val, and doesn't set it leading to a null pointer\ndereference when __ris_msmon_read() adds to it. This results in a kernel\noops with a call trace such as:\n\nCall trace:\n__ris_msmon_read+0x19c/0x64c (P)\nmpam_restore_mbwu_state+0xa0/0xe8\nsmp_call_on_cpu_callback+0x1c/0x38\nprocess_one_work+0x154/0x4b4\nworker_thread+0x188/0x310\nkthread+0x11c/0x130\nret_from_fork+0x10/0x20\n\nProvide a local variable for val to avoid __ris_msmon_read() dereferencing\na null pointer when adding to val."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"41e8a14950e1732af51cfec8fa09f8ded02a5ca9","status":"affected","lessThan":"ac3e12bc195786d3d44d730b5b2259fd36191848","versionType":"git"},{"version":"41e8a14950e1732af51cfec8fa09f8ded02a5ca9","status":"affected","lessThan":"4ad79c874e53ebb7fe3b8ae7ac6c858a2121f415","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/resctrl/mpam_devices.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.19","versionType":"semver"},{"version":"6.19.10","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/resctrl/mpam_devices.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/ac3e12bc195786d3d44d730b5b2259fd36191848"},{"url":"https://git.kernel.org/stable/c/4ad79c874e53ebb7fe3b8ae7ac6c858a2121f415"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T22:06:48.863Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19","versionEndExcluding":"6.19.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19","versionEndExcluding":"7.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}