{"api_version":"1","generated_at":"2026-06-10T13:42:07+00:00","cve":"CVE-2026-9076","urls":{"html":"https://cve.report/CVE-2026-9076","api":"https://cve.report/api/cve/CVE-2026-9076.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-9076","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-9076"},"summary":{"title":"Out-of-Bounds Read in CMS Password-Based Decryption","description":"Issue summary: When CMS password-based decryption (RFC 3211 / PWRI key unwrap)\nprocesses attacker-supplied CMS data, an attacker-chosen stream-mode KEK\ncipher can trigger a heap out-of-bounds read in kek_unwrap_key().\n\nImpact summary: A heap buffer over-read may trigger a crash which leads to\nDenial of Service for an application if the input buffer ends at a memory\npage boundary and the following page is unmapped. There is no information\ndisclosure as the over-read bytes are not revealed to the attacker.\n\nThe key unwrapping function performs a check-byte test as specified in the\nRFC that reads 7 bytes from a heap allocation that is based on the wrapped\nkey length from the message. There is a minimum length check based on the\nblock length of the wrapping cipher. However the cipher is selected from\nan OID carried in the attacker's PWRI keyEncryptionAlgorithm with no\nrequirement that the cipher be a block cipher. When an attacker selects\na stream-mode cipher the guard will be ineffective and the allocated buffer\ncontaining the unwrapped key can be too small to fit the check-bytes\nspecified in the RFC and a buffer over-read can happen.\n\nApplications calling CMS_decrypt() or CMS_decrypt_set1_password()\n(equivalently openssl cms -decrypt -pwri_password ...) on untrusted CMS\ndata are vulnerable to this issue. No password knowledge is required: the\nover-read happens during the unwrap attempt before any authentication\nsucceeds.\n\nThe over-read is limited to a few bytes and is not written to output, so\nthere is no information disclosure. Triggering a crash requires the\nallocation to border unmapped memory, which is unlikely with the normal\nallocator.\n\nThe FIPS modules are not affected by this issue.","state":"PUBLISHED","assigner":"openssl","published_at":"2026-06-09 17:17:50","updated_at":"2026-06-10 08:16:26"},"problem_types":["CWE-125","CWE-125 CWE-125 Out-of-bounds Read"],"metrics":[{"version":"3.1","source":"ADP","type":"DECLARED","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}},{"version":"3.1","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","type":"Secondary","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}}],"references":[{"url":"https://github.com/openssl/openssl/commit/715349a1d7c6db970e6815dafb90915f07307f98","name":"https://github.com/openssl/openssl/commit/715349a1d7c6db970e6815dafb90915f07307f98","refsource":"openssl-security@openssl.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/openssl/openssl/commit/77bf00ab13f6ff5e516535432f0328ed70ec0c26","name":"https://github.com/openssl/openssl/commit/77bf00ab13f6ff5e516535432f0328ed70ec0c26","refsource":"openssl-security@openssl.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://openssl-library.org/news/secadv/20260609.txt","name":"https://openssl-library.org/news/secadv/20260609.txt","refsource":"openssl-security@openssl.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/openssl/openssl/commit/05b066366842f930fadd9a6e94df98030af431bb","name":"https://github.com/openssl/openssl/commit/05b066366842f930fadd9a6e94df98030af431bb","refsource":"openssl-security@openssl.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/openssl/openssl/commit/3d8d5bc1056b2f62da9fede23fedbf47e85187b0","name":"https://github.com/openssl/openssl/commit/3d8d5bc1056b2f62da9fede23fedbf47e85187b0","refsource":"openssl-security@openssl.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/openssl/openssl/commit/eecbe330977e8d023aae1ca2d9bdbe983ef3fdc6","name":"https://github.com/openssl/openssl/commit/eecbe330977e8d023aae1ca2d9bdbe983ef3fdc6","refsource":"openssl-security@openssl.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/openssl/security/commit/05b066366842f930fadd9a6e94df98030af431bb","name":"https://github.com/openssl/security/commit/05b066366842f930fadd9a6e94df98030af431bb","refsource":"MITRE","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/openssl/security/commit/3d8d5bc1056b2f62da9fede23fedbf47e85187b0","name":"https://github.com/openssl/security/commit/3d8d5bc1056b2f62da9fede23fedbf47e85187b0","refsource":"MITRE","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/openssl/security/commit/715349a1d7c6db970e6815dafb90915f07307f98","name":"https://github.com/openssl/security/commit/715349a1d7c6db970e6815dafb90915f07307f98","refsource":"MITRE","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/openssl/security/commit/77bf00ab13f6ff5e516535432f0328ed70ec0c26","name":"https://github.com/openssl/security/commit/77bf00ab13f6ff5e516535432f0328ed70ec0c26","refsource":"MITRE","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/openssl/security/commit/eecbe330977e8d023aae1ca2d9bdbe983ef3fdc6","name":"https://github.com/openssl/security/commit/eecbe330977e8d023aae1ca2d9bdbe983ef3fdc6","refsource":"MITRE","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-9076","name":"CVE 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custom","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[{"source":"CNA","value":"Bhabani Sankar Das","lang":"en"},{"source":"CNA","value":"Haruki Oyama (Waseda University)","lang":"en"},{"source":"CNA","value":"Nikola Pajkovsky","lang":"en"}],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}},{"other":{"content":{"id":"CVE-2026-9076","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA 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Sankar Das"},{"lang":"en","type":"reporter","value":"Haruki Oyama (Waseda University)"},{"lang":"en","type":"remediation developer","value":"Nikola Pajkovsky"}],"datePublic":"2026-06-09T14:00:00.000Z","descriptions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"Issue summary: When CMS password-based decryption (RFC 3211 / PWRI key unwrap)<br>processes attacker-supplied CMS data, an attacker-chosen stream-mode KEK<br>cipher can trigger a heap out-of-bounds read in kek_unwrap_key().<br><br>Impact summary: A heap buffer over-read may trigger a crash which leads to<br>Denial of Service for an application if the input buffer ends at a memory<br>page boundary and the following page is unmapped. There is no information<br>disclosure as the over-read bytes are not revealed to the attacker.<br><br>The key unwrapping function performs a check-byte test as specified in the<br>RFC that reads 7 bytes from a heap allocation that is based on the wrapped<br>key length from the message. There is a minimum length check based on the<br>block length of the wrapping cipher. However the cipher is selected from<br>an OID carried in the attacker's PWRI keyEncryptionAlgorithm with no<br>requirement that the cipher be a block cipher. When an attacker selects<br>a stream-mode cipher the guard will be ineffective and the allocated buffer<br>containing the unwrapped key can be too small to fit the check-bytes<br>specified in the RFC and a buffer over-read can happen.<br><br>Applications calling CMS_decrypt() or CMS_decrypt_set1_password()<br>(equivalently openssl cms -decrypt -pwri_password ...) on untrusted CMS<br>data are vulnerable to this issue. No password knowledge is required: the<br>over-read happens during the unwrap attempt before any authentication<br>succeeds.<br><br>The over-read is limited to a few bytes and is not written to output, so<br>there is no information disclosure. Triggering a crash requires the<br>allocation to border unmapped memory, which is unlikely with the normal<br>allocator.<br><br>The FIPS modules are not affected by this issue."}],"value":"Issue summary: When CMS password-based decryption (RFC 3211 / PWRI key unwrap)\nprocesses attacker-supplied CMS data, an attacker-chosen stream-mode KEK\ncipher can trigger a heap out-of-bounds read in kek_unwrap_key().\n\nImpact summary: A heap buffer over-read may trigger a crash which leads to\nDenial of Service for an application if the input buffer ends at a memory\npage boundary and the following page is unmapped. There is no information\ndisclosure as the over-read bytes are not revealed to the attacker.\n\nThe key unwrapping function performs a check-byte test as specified in the\nRFC that reads 7 bytes from a heap allocation that is based on the wrapped\nkey length from the message. There is a minimum length check based on the\nblock length of the wrapping cipher. However the cipher is selected from\nan OID carried in the attacker's PWRI keyEncryptionAlgorithm with no\nrequirement that the cipher be a block cipher. When an attacker selects\na stream-mode cipher the guard will be ineffective and the allocated buffer\ncontaining the unwrapped key can be too small to fit the check-bytes\nspecified in the RFC and a buffer over-read can happen.\n\nApplications calling CMS_decrypt() or CMS_decrypt_set1_password()\n(equivalently openssl cms -decrypt -pwri_password ...) on untrusted CMS\ndata are vulnerable to this issue. No password knowledge is required: the\nover-read happens during the unwrap attempt before any authentication\nsucceeds.\n\nThe over-read is limited to a few bytes and is not written to output, so\nthere is no information disclosure. Triggering a crash requires the\nallocation to border unmapped memory, which is unlikely with the normal\nallocator.\n\nThe FIPS modules are not affected by this issue."}],"metrics":[{"format":"other","other":{"content":{"text":"Low"},"type":"https://openssl-library.org/policies/general/security-policy/"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-125","description":"CWE-125 Out-of-bounds Read","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-06-10T07:47:51.139Z","orgId":"3a12439a-ef3a-4c79-92e6-6081a721f1e5","shortName":"openssl"},"references":[{"name":"OpenSSL Advisory","tags":["vendor-advisory"],"url":"https://openssl-library.org/news/secadv/20260609.txt"},{"name":"4.0.1 git commit","tags":["patch"],"url":"https://github.com/openssl/openssl/commit/3d8d5bc1056b2f62da9fede23fedbf47e85187b0"},{"name":"3.6.3 git commit","tags":["patch"],"url":"https://github.com/openssl/openssl/commit/77bf00ab13f6ff5e516535432f0328ed70ec0c26"},{"name":"3.5.7 git commit","tags":["patch"],"url":"https://github.com/openssl/openssl/commit/715349a1d7c6db970e6815dafb90915f07307f98"},{"name":"3.4.6 git commit","tags":["patch"],"url":"https://github.com/openssl/openssl/commit/05b066366842f930fadd9a6e94df98030af431bb"},{"name":"3.0.21 git commit","tags":["patch"],"url":"https://github.com/openssl/openssl/commit/eecbe330977e8d023aae1ca2d9bdbe983ef3fdc6"}],"source":{"discovery":"UNKNOWN"},"title":"Out-of-Bounds Read in CMS Password-Based Decryption","x_generator":{"engine":"Vulnogram 0.2.0"}}},"cveMetadata":{"assignerOrgId":"3a12439a-ef3a-4c79-92e6-6081a721f1e5","assignerShortName":"openssl","cveId":"CVE-2026-9076","datePublished":"2026-06-09T16:03:16.306Z","dateReserved":"2026-05-20T12:43:37.677Z","dateUpdated":"2026-06-10T07:47:51.139Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-06-09 17:17:50","lastModifiedDate":"2026-06-10 08:16:26","problem_types":["CWE-125","CWE-125 CWE-125 Out-of-bounds Read"],"metrics":{"cvssMetricV31":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"9076","Ordinal":"1","Title":"Out-of-Bounds Read in CMS Password-Based Decryption","CVE":"CVE-2026-9076","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"9076","Ordinal":"1","NoteData":"Issue summary: When CMS password-based decryption (RFC 3211 / PWRI key unwrap)\nprocesses attacker-supplied CMS data, an attacker-chosen stream-mode KEK\ncipher can trigger a heap out-of-bounds read in kek_unwrap_key().\n\nImpact summary: A heap buffer over-read may trigger a crash which leads to\nDenial of Service for an application if the input buffer ends at a memory\npage boundary and the following page is unmapped. There is no information\ndisclosure as the over-read bytes are not revealed to the attacker.\n\nThe key unwrapping function performs a check-byte test as specified in the\nRFC that reads 7 bytes from a heap allocation that is based on the wrapped\nkey length from the message. There is a minimum length check based on the\nblock length of the wrapping cipher. However the cipher is selected from\nan OID carried in the attacker's PWRI keyEncryptionAlgorithm with no\nrequirement that the cipher be a block cipher. When an attacker selects\na stream-mode cipher the guard will be ineffective and the allocated buffer\ncontaining the unwrapped key can be too small to fit the check-bytes\nspecified in the RFC and a buffer over-read can happen.\n\nApplications calling CMS_decrypt() or CMS_decrypt_set1_password()\n(equivalently openssl cms -decrypt -pwri_password ...) on untrusted CMS\ndata are vulnerable to this issue. No password knowledge is required: the\nover-read happens during the unwrap attempt before any authentication\nsucceeds.\n\nThe over-read is limited to a few bytes and is not written to output, so\nthere is no information disclosure. Triggering a crash requires the\nallocation to border unmapped memory, which is unlikely with the normal\nallocator.\n\nThe FIPS modules are not affected by this issue.","Type":"Description","Title":"Out-of-Bounds Read in CMS Password-Based Decryption"}]}}}