{"api_version":"1","generated_at":"2026-09-17T07:14:46+00:00","cve":"CVE-2026-89923","urls":{"html":"https://cve.report/CVE-2026-89923","api":"https://cve.report/api/cve/CVE-2026-89923.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-89923","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-89923"},"summary":{"title":"KVM: s390: Free guest debug data on vcpu destroy","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: s390: Free guest debug data on vcpu destroy\n\nkvm_s390_clear_bp_data() is only called from\nkvm_arch_vcpu_ioctl_set_guest_debug(), i.e. when user space changes or\ndisables debugging. A vCPU that is destroyed while hardware breakpoints\nare still armed - the normal case when the VMM just exits or crashes -\nleaks hw_bp_info, hw_wp_info and all old_data buffers, since generic KVM\nfrees the vCPU right after kvm_arch_vcpu_destroy().\n\nThat is bounded by MAX_BP_COUNT entries, so roughly 8 KiB per vCPU, but\nit is unbounded over VM lifetimes. The allocations are\nGFP_KERNEL_ACCOUNT, so the charge also outlives the exiting process and\npins dying memcgs.\n\nFix by clearing the debug data on vCPU destruction. Calling it\nunconditionally is fine: struct kvm_vcpu is zero allocated, so for a vCPU\nthat never enabled debugging the counters are 0 and the pointers NULL.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-16 11:17:01","updated_at":"2026-09-16 11:17:01"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/e7f698b09d4a7c36b299acf680fc50fe868e2bcd","name":"https://git.kernel.org/stable/c/e7f698b09d4a7c36b299acf680fc50fe868e2bcd","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6c996b12bbe4a6023076e8eee3cfaf2cc99db76c","name":"https://git.kernel.org/stable/c/6c996b12bbe4a6023076e8eee3cfaf2cc99db76c","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/9a32c4c6a6c23b7f5bf765eb5b83ba7f64a8ec63","name":"https://git.kernel.org/stable/c/9a32c4c6a6c23b7f5bf765eb5b83ba7f64a8ec63","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/544a5a665019cef394ce8bda97fa7a2cab253781","name":"https://git.kernel.org/stable/c/544a5a665019cef394ce8bda97fa7a2cab253781","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/e4d8b7f176b976474e0800ba71ee2dfa3ce263c9","name":"https://git.kernel.org/stable/c/e4d8b7f176b976474e0800ba71ee2dfa3ce263c9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/053f2068cf9b0654b651fed5ad7649d3deb982bf","name":"https://git.kernel.org/stable/c/053f2068cf9b0654b651fed5ad7649d3deb982bf","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b5acacfdb8966abff91836c1c5bd7da59d8a526e","name":"https://git.kernel.org/stable/c/b5acacfdb8966abff91836c1c5bd7da59d8a526e","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d6280fc540d8f4653c9b54a78cb747e128070f5e","name":"https://git.kernel.org/stable/c/d6280fc540d8f4653c9b54a78cb747e128070f5e","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89923","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89923","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 27291e2165b6de70c476b7b675308113edd69a60 053f2068cf9b0654b651fed5ad7649d3deb982bf git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 27291e2165b6de70c476b7b675308113edd69a60 6c996b12bbe4a6023076e8eee3cfaf2cc99db76c git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 27291e2165b6de70c476b7b675308113edd69a60 d6280fc540d8f4653c9b54a78cb747e128070f5e git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 27291e2165b6de70c476b7b675308113edd69a60 544a5a665019cef394ce8bda97fa7a2cab253781 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 27291e2165b6de70c476b7b675308113edd69a60 9a32c4c6a6c23b7f5bf765eb5b83ba7f64a8ec63 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 27291e2165b6de70c476b7b675308113edd69a60 b5acacfdb8966abff91836c1c5bd7da59d8a526e git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 27291e2165b6de70c476b7b675308113edd69a60 e4d8b7f176b976474e0800ba71ee2dfa3ce263c9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 27291e2165b6de70c476b7b675308113edd69a60 e7f698b09d4a7c36b299acf680fc50fe868e2bcd git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3.16","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 3.16 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.10.270 5.10.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.221 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.188 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.157 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.110 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.51 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.5 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["arch/s390/kvm/kvm-s390.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"053f2068cf9b0654b651fed5ad7649d3deb982bf","status":"affected","version":"27291e2165b6de70c476b7b675308113edd69a60","versionType":"git"},{"lessThan":"6c996b12bbe4a6023076e8eee3cfaf2cc99db76c","status":"affected","version":"27291e2165b6de70c476b7b675308113edd69a60","versionType":"git"},{"lessThan":"d6280fc540d8f4653c9b54a78cb747e128070f5e","status":"affected","version":"27291e2165b6de70c476b7b675308113edd69a60","versionType":"git"},{"lessThan":"544a5a665019cef394ce8bda97fa7a2cab253781","status":"affected","version":"27291e2165b6de70c476b7b675308113edd69a60","versionType":"git"},{"lessThan":"9a32c4c6a6c23b7f5bf765eb5b83ba7f64a8ec63","status":"affected","version":"27291e2165b6de70c476b7b675308113edd69a60","versionType":"git"},{"lessThan":"b5acacfdb8966abff91836c1c5bd7da59d8a526e","status":"affected","version":"27291e2165b6de70c476b7b675308113edd69a60","versionType":"git"},{"lessThan":"e4d8b7f176b976474e0800ba71ee2dfa3ce263c9","status":"affected","version":"27291e2165b6de70c476b7b675308113edd69a60","versionType":"git"},{"lessThan":"e7f698b09d4a7c36b299acf680fc50fe868e2bcd","status":"affected","version":"27291e2165b6de70c476b7b675308113edd69a60","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["arch/s390/kvm/kvm-s390.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"3.16"},{"lessThan":"3.16","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.10.*","status":"unaffected","version":"5.10.270","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.221","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.188","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.157","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.110","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.51","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.5","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.10.270","versionStartIncluding":"3.16","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.221","versionStartIncluding":"3.16","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.188","versionStartIncluding":"3.16","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.157","versionStartIncluding":"3.16","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.110","versionStartIncluding":"3.16","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.51","versionStartIncluding":"3.16","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.5","versionStartIncluding":"3.16","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc1","versionStartIncluding":"3.16","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: s390: Free guest debug data on vcpu destroy\n\nkvm_s390_clear_bp_data() is only called from\nkvm_arch_vcpu_ioctl_set_guest_debug(), i.e. when user space changes or\ndisables debugging. A vCPU that is destroyed while hardware breakpoints\nare still armed - the normal case when the VMM just exits or crashes -\nleaks hw_bp_info, hw_wp_info and all old_data buffers, since generic KVM\nfrees the vCPU right after kvm_arch_vcpu_destroy().\n\nThat is bounded by MAX_BP_COUNT entries, so roughly 8 KiB per vCPU, but\nit is unbounded over VM lifetimes. The allocations are\nGFP_KERNEL_ACCOUNT, so the charge also outlives the exiting process and\npins dying memcgs.\n\nFix by clearing the debug data on vCPU destruction. Calling it\nunconditionally is fine: struct kvm_vcpu is zero allocated, so for a vCPU\nthat never enabled debugging the counters are 0 and the pointers NULL."}],"providerMetadata":{"dateUpdated":"2026-09-16T10:32:16.765Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/053f2068cf9b0654b651fed5ad7649d3deb982bf"},{"url":"https://git.kernel.org/stable/c/6c996b12bbe4a6023076e8eee3cfaf2cc99db76c"},{"url":"https://git.kernel.org/stable/c/d6280fc540d8f4653c9b54a78cb747e128070f5e"},{"url":"https://git.kernel.org/stable/c/544a5a665019cef394ce8bda97fa7a2cab253781"},{"url":"https://git.kernel.org/stable/c/9a32c4c6a6c23b7f5bf765eb5b83ba7f64a8ec63"},{"url":"https://git.kernel.org/stable/c/b5acacfdb8966abff91836c1c5bd7da59d8a526e"},{"url":"https://git.kernel.org/stable/c/e4d8b7f176b976474e0800ba71ee2dfa3ce263c9"},{"url":"https://git.kernel.org/stable/c/e7f698b09d4a7c36b299acf680fc50fe868e2bcd"}],"title":"KVM: s390: Free guest debug data on vcpu destroy","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-89923","datePublished":"2026-09-16T10:32:16.765Z","dateReserved":"2026-09-11T19:38:34.775Z","dateUpdated":"2026-09-16T10:32:16.765Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-16 11:17:01","lastModifiedDate":"2026-09-16 11:17:01","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"89923","Ordinal":"1","Title":"KVM: s390: Free guest debug data on vcpu destroy","CVE":"CVE-2026-89923","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"89923","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: s390: Free guest debug data on vcpu destroy\n\nkvm_s390_clear_bp_data() is only called from\nkvm_arch_vcpu_ioctl_set_guest_debug(), i.e. when user space changes or\ndisables debugging. A vCPU that is destroyed while hardware breakpoints\nare still armed - the normal case when the VMM just exits or crashes -\nleaks hw_bp_info, hw_wp_info and all old_data buffers, since generic KVM\nfrees the vCPU right after kvm_arch_vcpu_destroy().\n\nThat is bounded by MAX_BP_COUNT entries, so roughly 8 KiB per vCPU, but\nit is unbounded over VM lifetimes. The allocations are\nGFP_KERNEL_ACCOUNT, so the charge also outlives the exiting process and\npins dying memcgs.\n\nFix by clearing the debug data on vCPU destruction. Calling it\nunconditionally is fine: struct kvm_vcpu is zero allocated, so for a vCPU\nthat never enabled debugging the counters are 0 and the pointers NULL.","Type":"Description","Title":"KVM: s390: Free guest debug data on vcpu destroy"}]}}}