{"api_version":"1","generated_at":"2026-11-03T18:06:07+00:00","cve":"CVE-2026-120758","urls":{"html":"https://cve.report/CVE-2026-120758","api":"https://cve.report/api/cve/CVE-2026-120758.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-120758","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-120758"},"summary":{"title":"NULL Pointer Dereference in H5HL_unprotect via Corrupted File","description":"HDF5 through 2.2.0 contains a NULL pointer dereference vulnerability in H5HL_unprotect() in src/H5HL.c. H5HL_protect() pins a single metadata cache entry for a local heap, either the heap prefix or the separate data block, and H5HL_unprotect() unpins it on the final unprotect. When the metadata cache destroys a corrupted local heap entry, H5HL__prfx_dest() unlinks it from the heap by setting heap->prfx or heap->dblk to NULL. A crafted HDF5 file can therefore reach H5HL_unprotect() with no cached object to unpin, and the function passes the NULL pointer to H5AC_unpin_entry(). This causes an assertion failure in debug builds and a NULL pointer dereference and crash in release builds. An attacker who can get a user or application to open and traverse a malicious file can cause a denial of service.","state":"PUBLISHED","assigner":"HDFG","published_at":"2026-11-03 16:17:23","updated_at":"2026-11-03 16:30:17"},"problem_types":["CWE-476","CWE-476 CWE-476 NULL pointer dereference"],"metrics":[{"version":"4.0","source":"0253b833-3e77-4dfe-9d57-17db1a2f0a74","type":"Secondary","score":"5.4","severity":"MEDIUM","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","data":{"version":"4.0","vectorString":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","baseScore":5.4,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"PASSIVE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"PROOF_OF_CONCEPT","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}},{"version":"4.0","source":"CNA","type":"CVSS","score":"5.4","severity":"MEDIUM","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P","data":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"LOCAL","baseScore":5.4,"baseSeverity":"MEDIUM","exploitMaturity":"PROOF_OF_CONCEPT","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"PASSIVE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P","version":"4.0","vulnAvailabilityImpact":"HIGH","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnerabilityResponseEffort":"NOT_DEFINED"}}],"references":[{"url":"https://github.com/HDFGroup/hdf5/pull/6377","name":"https://github.com/HDFGroup/hdf5/pull/6377","refsource":"0253b833-3e77-4dfe-9d57-17db1a2f0a74","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-120758","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-120758","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"The HDF Group","product":"HDF5","version":"affected < 2.3.0","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":"HDF5","vendor":"The HDF Group","versions":[{"status":"affected","version":"< 2.3.0"}]}],"descriptions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"HDF5 through 2.2.0 contains a NULL pointer dereference vulnerability in <code>H5HL_unprotect()</code> in <code>src/H5HL.c</code>. <code>H5HL_protect()</code> pins a single metadata cache entry for a local heap, either the heap prefix or the separate data block, and <code>H5HL_unprotect()</code> unpins it on the final unprotect. When the metadata cache destroys a corrupted local heap entry, <code>H5HL__prfx_dest()</code> unlinks it from the heap by setting <code>heap-&gt;prfx</code> or <code>heap-&gt;dblk</code> to NULL. A crafted HDF5 file can therefore reach <code>H5HL_unprotect()</code> with no cached object to unpin, and the function passes the NULL pointer to <code>H5AC_unpin_entry()</code>. This causes an assertion failure in debug builds and a NULL pointer dereference and crash in release builds. An attacker who can get a user or application to open and traverse a malicious file can cause a denial of service.&nbsp;&nbsp;"}],"value":"HDF5 through 2.2.0 contains a NULL pointer dereference vulnerability in H5HL_unprotect() in src/H5HL.c. H5HL_protect() pins a single metadata cache entry for a local heap, either the heap prefix or the separate data block, and H5HL_unprotect() unpins it on the final unprotect. When the metadata cache destroys a corrupted local heap entry, H5HL__prfx_dest() unlinks it from the heap by setting heap->prfx or heap->dblk to NULL. A crafted HDF5 file can therefore reach H5HL_unprotect() with no cached object to unpin, and the function passes the NULL pointer to H5AC_unpin_entry(). This causes an assertion failure in debug builds and a NULL pointer dereference and crash in release builds. An attacker who can get a user or application to open and traverse a malicious file can cause a denial of service."}],"impacts":[{"capecId":"CAPEC-153","descriptions":[{"lang":"en","value":"CAPEC-153 Input Data Manipulation"}]}],"metrics":[{"cvssV4_0":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"LOCAL","baseScore":5.4,"baseSeverity":"MEDIUM","exploitMaturity":"PROOF_OF_CONCEPT","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"PASSIVE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P","version":"4.0","vulnAvailabilityImpact":"HIGH","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnerabilityResponseEffort":"NOT_DEFINED"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-476","description":"CWE-476 NULL pointer dereference","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-11-03T15:38:09.387Z","orgId":"0253b833-3e77-4dfe-9d57-17db1a2f0a74","shortName":"HDFG"},"references":[{"url":"https://github.com/HDFGroup/hdf5/pull/6377"}],"source":{"discovery":"UNKNOWN"},"title":"NULL Pointer Dereference in H5HL_unprotect via Corrupted File","x_generator":{"engine":"Vulnogram 1.0.5"}}},"cveMetadata":{"assignerOrgId":"0253b833-3e77-4dfe-9d57-17db1a2f0a74","assignerShortName":"HDFG","cveId":"CVE-2026-120758","datePublished":"2026-11-03T15:38:09.387Z","dateReserved":"2026-11-02T21:30:12.341Z","dateUpdated":"2026-11-03T15:38:09.387Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-11-03 16:17:23","lastModifiedDate":"2026-11-03 16:30:17","problem_types":["CWE-476","CWE-476 CWE-476 NULL pointer dereference"],"metrics":{"cvssMetricV40":[{"source":"0253b833-3e77-4dfe-9d57-17db1a2f0a74","type":"Secondary","cvssData":{"version":"4.0","vectorString":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","baseScore":5.4,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"PASSIVE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"PROOF_OF_CONCEPT","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"120758","Ordinal":"1","Title":"NULL Pointer Dereference in H5HL_unprotect via Corrupted File","CVE":"CVE-2026-120758","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"120758","Ordinal":"1","NoteData":"HDF5 through 2.2.0 contains a NULL pointer dereference vulnerability in H5HL_unprotect() in src/H5HL.c. H5HL_protect() pins a single metadata cache entry for a local heap, either the heap prefix or the separate data block, and H5HL_unprotect() unpins it on the final unprotect. When the metadata cache destroys a corrupted local heap entry, H5HL__prfx_dest() unlinks it from the heap by setting heap->prfx or heap->dblk to NULL. A crafted HDF5 file can therefore reach H5HL_unprotect() with no cached object to unpin, and the function passes the NULL pointer to H5AC_unpin_entry(). This causes an assertion failure in debug builds and a NULL pointer dereference and crash in release builds. An attacker who can get a user or application to open and traverse a malicious file can cause a denial of service.","Type":"Description","Title":"NULL Pointer Dereference in H5HL_unprotect via Corrupted File"}]}}}