{"api_version":"1","generated_at":"2026-10-26T07:02:47+00:00","cve":"CVE-2026-97922","urls":{"html":"https://cve.report/CVE-2026-97922","api":"https://cve.report/api/cve/CVE-2026-97922.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-97922","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-97922"},"summary":{"title":"tracing: Free histogram var refs regardless of how often they are referenced","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Free histogram var refs regardless of how often they are referenced\n\nUsing the same variable three or more times in one hist trigger leaks the\nvariable reference and its strings when the trigger is removed.\n\ncommit 656fe2ba85e8 (\"tracing: Use hist trigger's var_ref array to destroy\nvar_refs\") made a trigger's var_refs[] array the only owner of a var ref:\ndestroy_hist_field() returns early for HIST_FIELD_FL_VAR_REF, so the field\nexpressions never destroy one. One entry, freed once, no count needed.\n\ncommit 8bcebc77e85f (\"tracing: Fix histogram code when expression has same\nvar as value\") then made repeated references share one object and added a\ncount of them. Only the increment side exists, since those expressions\nstill return early and never drop a reference, so __destroy_hist_field()\nsees how many references were created rather than how many are left. It\nfrees when the decremented count is 0 or 1, so two references work and\nthree or more leak.\n\nSharing kept one array entry per object, and create_var_ref() searches and\nappends within a single trigger, so nothing outside it holds the object.\nRemoving a trigger whose variables are still referenced is already refused\nby check_var_refs() with -EBUSY. Drop the count and free unconditionally.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-25 11:17:19","updated_at":"2026-10-19 10:17:42"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/e7b6d67b43caee9183a4374d23641578ea556e6c","name":"https://git.kernel.org/stable/c/e7b6d67b43caee9183a4374d23641578ea556e6c","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/4bddcb346a6cf4615ca77f69a589623b877ca267","name":"https://git.kernel.org/stable/c/4bddcb346a6cf4615ca77f69a589623b877ca267","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b513a4c60a7aa1f4b4c2a48544ab003cb36f1e94","name":"https://git.kernel.org/stable/c/b513a4c60a7aa1f4b4c2a48544ab003cb36f1e94","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/a1f1d64a0a9791c842c4646253daf6ac0313eac7","name":"https://git.kernel.org/stable/c/a1f1d64a0a9791c842c4646253daf6ac0313eac7","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/94bbd65da4ae26592fa1977a74ee94218ab02a26","name":"https://git.kernel.org/stable/c/94bbd65da4ae26592fa1977a74ee94218ab02a26","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/4cff53bb19412c6f2d90b50678de5c3903f7f96a","name":"https://git.kernel.org/stable/c/4cff53bb19412c6f2d90b50678de5c3903f7f96a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-97922","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-97922","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8bcebc77e85f3d7536f96845a0fe94b1dddb6af0 a1f1d64a0a9791c842c4646253daf6ac0313eac7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8bcebc77e85f3d7536f96845a0fe94b1dddb6af0 b513a4c60a7aa1f4b4c2a48544ab003cb36f1e94 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8bcebc77e85f3d7536f96845a0fe94b1dddb6af0 e7b6d67b43caee9183a4374d23641578ea556e6c git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8bcebc77e85f3d7536f96845a0fe94b1dddb6af0 4cff53bb19412c6f2d90b50678de5c3903f7f96a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 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semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.189 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.158 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.111 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.53 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.7 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"97922","cve":"CVE-2026-97922","epss":"0.002050000","percentile":"0.095610000","score_date":"2026-10-05","updated_at":"2026-10-06 00:14:18"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["kernel/trace/trace_events_hist.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"a1f1d64a0a9791c842c4646253daf6ac0313eac7","status":"affected","version":"8bcebc77e85f3d7536f96845a0fe94b1dddb6af0","versionType":"git"},{"lessThan":"b513a4c60a7aa1f4b4c2a48544ab003cb36f1e94","status":"affected","version":"8bcebc77e85f3d7536f96845a0fe94b1dddb6af0","versionType":"git"},{"lessThan":"e7b6d67b43caee9183a4374d23641578ea556e6c","status":"affected","version":"8bcebc77e85f3d7536f96845a0fe94b1dddb6af0","versionType":"git"},{"lessThan":"4cff53bb19412c6f2d90b50678de5c3903f7f96a","status":"affected","version":"8bcebc77e85f3d7536f96845a0fe94b1dddb6af0","versionType":"git"},{"lessThan":"94bbd65da4ae26592fa1977a74ee94218ab02a26","status":"affected","version":"8bcebc77e85f3d7536f96845a0fe94b1dddb6af0","versionType":"git"},{"lessThan":"4bddcb346a6cf4615ca77f69a589623b877ca267","status":"affected","version":"8bcebc77e85f3d7536f96845a0fe94b1dddb6af0","versionType":"git"},{"status":"affected","version":"ce28d664054df01997baace61d1defca77689798","versionType":"git"},{"status":"affected","version":"bf470f051556b610265ea02ad2102de75e8e619c","versionType":"git"},{"lessThan":"4.20","status":"affected","version":"4.19.100","versionType":"semver"},{"lessThan":"5.5","status":"affected","version":"5.4.16","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["kernel/trace/trace_events_hist.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.5"},{"lessThan":"5.5","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.189","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.158","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.111","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.53","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.7","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.189","versionStartIncluding":"5.5","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.158","versionStartIncluding":"5.5","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.111","versionStartIncluding":"5.5","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.53","versionStartIncluding":"5.5","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.7","versionStartIncluding":"5.5","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3","versionStartIncluding":"5.5","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19.100","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4.16","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Free histogram var refs regardless of how often they are referenced\n\nUsing the same variable three or more times in one hist trigger leaks the\nvariable reference and its strings when the trigger is removed.\n\ncommit 656fe2ba85e8 (\"tracing: Use hist trigger's var_ref array to destroy\nvar_refs\") made a trigger's var_refs[] array the only owner of a var ref:\ndestroy_hist_field() returns early for HIST_FIELD_FL_VAR_REF, so the field\nexpressions never destroy one. One entry, freed once, no count needed.\n\ncommit 8bcebc77e85f (\"tracing: Fix histogram code when expression has same\nvar as value\") then made repeated references share one object and added a\ncount of them. Only the increment side exists, since those expressions\nstill return early and never drop a reference, so __destroy_hist_field()\nsees how many references were created rather than how many are left. It\nfrees when the decremented count is 0 or 1, so two references work and\nthree or more leak.\n\nSharing kept one array entry per object, and create_var_ref() searches and\nappends within a single trigger, so nothing outside it holds the object.\nRemoving a trigger whose variables are still referenced is already refused\nby check_var_refs() with -EBUSY. Drop the count and free unconditionally."}],"providerMetadata":{"dateUpdated":"2026-10-19T09:10:49.154Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/a1f1d64a0a9791c842c4646253daf6ac0313eac7"},{"url":"https://git.kernel.org/stable/c/b513a4c60a7aa1f4b4c2a48544ab003cb36f1e94"},{"url":"https://git.kernel.org/stable/c/e7b6d67b43caee9183a4374d23641578ea556e6c"},{"url":"https://git.kernel.org/stable/c/4cff53bb19412c6f2d90b50678de5c3903f7f96a"},{"url":"https://git.kernel.org/stable/c/94bbd65da4ae26592fa1977a74ee94218ab02a26"},{"url":"https://git.kernel.org/stable/c/4bddcb346a6cf4615ca77f69a589623b877ca267"}],"title":"tracing: Free histogram var refs regardless of how often they are referenced","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-97922","datePublished":"2026-09-25T10:22:41.699Z","dateReserved":"2026-09-25T10:18:58.202Z","dateUpdated":"2026-10-19T09:10:49.154Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-25 11:17:19","lastModifiedDate":"2026-10-19 10:17:42","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"97922","Ordinal":"1","Title":"tracing: Free histogram var refs regardless of how often they ar","CVE":"CVE-2026-97922","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"97922","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Free histogram var refs regardless of how often they are referenced\n\nUsing the same variable three or more times in one hist trigger leaks the\nvariable reference and its strings when the trigger is removed.\n\ncommit 656fe2ba85e8 (\"tracing: Use hist trigger's var_ref array to destroy\nvar_refs\") made a trigger's var_refs[] array the only owner of a var ref:\ndestroy_hist_field() returns early for HIST_FIELD_FL_VAR_REF, so the field\nexpressions never destroy one. One entry, freed once, no count needed.\n\ncommit 8bcebc77e85f (\"tracing: Fix histogram code when expression has same\nvar as value\") then made repeated references share one object and added a\ncount of them. Only the increment side exists, since those expressions\nstill return early and never drop a reference, so __destroy_hist_field()\nsees how many references were created rather than how many are left. It\nfrees when the decremented count is 0 or 1, so two references work and\nthree or more leak.\n\nSharing kept one array entry per object, and create_var_ref() searches and\nappends within a single trigger, so nothing outside it holds the object.\nRemoving a trigger whose variables are still referenced is already refused\nby check_var_refs() with -EBUSY. Drop the count and free unconditionally.","Type":"Description","Title":"tracing: Free histogram var refs regardless of how often they ar"}]}}}