{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-75805", "assignerOrgId": "3a12439a-ef3a-4c79-92e6-6081a721f1e5", "state": "PUBLISHED", "assignerShortName": "openssl", "dateReserved": "2026-08-18T09:34:32.659Z", "datePublished": "2026-09-29T15:32:20.408Z", "dateUpdated": "2026-11-10T12:49:43.797Z" }, "containers": { "cna": { "affected": [ { "defaultStatus": "unaffected", "product": "OpenSSL", "vendor": "OpenSSL", "versions": [ { "lessThan": "4.0.3", "status": "affected", "version": "4.0.0", "versionType": "semver" }, { "lessThan": "3.6.5", "status": "affected", "version": "3.6.0", "versionType": "semver" }, { "lessThan": "3.5.9", "status": "affected", "version": "3.5.0", "versionType": "semver" }, { "lessThan": "3.4.8", "status": "affected", "version": "3.4.0", "versionType": "semver" }, { "lessThan": "3.0.23", "status": "affected", "version": "3.0.0", "versionType": "semver" } ] } ], "credits": [ { "lang": "en", "type": "reporter", "value": "Bhabani Sankar Das" }, { "lang": "en", "type": "remediation developer", "value": "Bhabani Sankar Das" }, { "lang": "en", "type": "remediation developer", "value": "Norbert Pocs" } ], "datePublic": "2026-09-29T14:21:57.000Z", "descriptions": [ { "lang": "en", "supportingMedia": [ { "base64": false, "type": "text/html", "value": "Issue summary: A CMP client that requests certificate revocation on the basis
of a PKCS#10 CSR may dereference a NULL pointer and terminate abnormally when
processing a crafted revocation response.

Impact summary: The NULL pointer dereference happens on a read which
leads to a crash and a Denial of Service for the affected client application.

CWE: CWE-476: NULL-pointer dereference

Description: A CMP client revoking a certificate has to tell the server which
certificate to revoke, and may do so by supplying a PKCS#10 CSR instead of the
certificate itself or its issuer name and serial number. This is
'openssl cmp -cmd rr -csr ' on the command line, or
OSSL_CMP_exec_RR_ses() with the certificate supplied via
OSSL_CMP_CTX_set1_p10CSR() through the API.

A CSR does not contain the issuer name and serial number of the certificate,
so the client does not send them. A server may optionally name the
certificate it revoked in its response, and the client then compares that
name against what it sent. Having sent neither an issuer name nor a serial
number, it has nothing to compare against, and a server returning a specially
crafted name causes the client to read from a NULL pointer and crash.

The revocation response is checked for valid message protection before
the affected code is reached, so an attacker must be a malicious or
compromised CMP server, or a man-in-the-middle in possession of the
secret used for message protection. Clients that identify the certificate
to be revoked by a certificate or by issuer and serial number rather
than by a PKCS#10 CSR are not affected.

FIPS impact: no
No FIPS modules are affected by this issue, as the CMP protocol
implementation is outside the OpenSSL FIPS module boundary." } ], "value": "Issue summary: A CMP client that requests certificate revocation on the basis\nof a PKCS#10 CSR may dereference a NULL pointer and terminate abnormally when\nprocessing a crafted revocation response. \n\nImpact summary: The NULL pointer dereference happens on a read which \nleads to a crash and a Denial of Service for the affected client application.\n\nCWE: CWE-476: NULL-pointer dereference\n\nDescription: A CMP client revoking a certificate has to tell the server which\ncertificate to revoke, and may do so by supplying a PKCS#10 CSR instead of the\ncertificate itself or its issuer name and serial number. This is\n'openssl cmp -cmd rr -csr ' on the command line, or\nOSSL_CMP_exec_RR_ses() with the certificate supplied via\nOSSL_CMP_CTX_set1_p10CSR() through the API.\n\nA CSR does not contain the issuer name and serial number of the certificate,\nso the client does not send them. A server may optionally name the\ncertificate it revoked in its response, and the client then compares that\nname against what it sent. Having sent neither an issuer name nor a serial\nnumber, it has nothing to compare against, and a server returning a specially\ncrafted name causes the client to read from a NULL pointer and crash.\n\nThe revocation response is checked for valid message protection before\nthe affected code is reached, so an attacker must be a malicious or\ncompromised CMP server, or a man-in-the-middle in possession of the\nsecret used for message protection. Clients that identify the certificate\nto be revoked by a certificate or by issuer and serial number rather\nthan by a PKCS#10 CSR are not affected.\n\nFIPS impact: no\nNo FIPS modules are affected by this issue, as the CMP protocol\nimplementation is outside the OpenSSL FIPS module boundary." } ], "metrics": [ { "format": "other", "other": { "content": { "text": "Low" }, "type": "https://openssl-library.org/policies/general/security-policy/" } } ], "problemTypes": [ { "descriptions": [ { "cweId": "CWE-476", "description": "CWE-476 NULL-pointer dereference", "lang": "en", "type": "CWE" } ] } ], "providerMetadata": { "orgId": "3a12439a-ef3a-4c79-92e6-6081a721f1e5", "shortName": "openssl", "dateUpdated": "2026-09-29T15:32:20.408Z" }, "references": [ { "name": "OpenSSL Advisory", "tags": [ "vendor-advisory" ], "url": "https://openssl-library.org/news/secadv/20260929.txt" }, { "name": "4.0.3 git commit", "tags": [ "patch" ], "url": "https://github.com/openssl/openssl/commit/7ca0ccb5172a577e9b87267d77bfe21e5481a5e7" }, { "name": "3.6.5 git commit", "tags": [ "patch" ], "url": "https://github.com/openssl/openssl/commit/7588db7fef14209c3caa3a101d11a02006b19166" }, { "name": "3.5.9 git commit", "tags": [ "patch" ], "url": "https://github.com/openssl/openssl/commit/9eb2a8a9b86136cdb39d6d7d50644dd66941cdc3" }, { "name": "3.4.8 git commit", "tags": [ "patch" ], "url": "https://github.com/openssl/openssl/commit/abf02872a4b71767ecc72293424420f5b009190f" } ], "source": { "discovery": "UNKNOWN" }, "title": "NULL Pointer Dereference in CMP Client Revocation Response Handling", "x_generator": { "engine": "Vulnogram 0.2.0" } }, "adp": [ { "metrics": [ { "cvssV3_1": { "scope": "UNCHANGED", "version": "3.1", "baseScore": 5.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "LOW", "privilegesRequired": "NONE", "confidentialityImpact": "NONE" } }, { "other": { "type": "ssvc", "content": { "timestamp": "2026-09-29T16:54:03.315064Z", "id": "CVE-2026-75805", "options": [ { "Exploitation": "none" }, { "Automatable": "yes" }, { "Technical Impact": "partial" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-29T16:54:39.263Z" } }, { "x_adpType": "supplier", "providerMetadata": { "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "shortName": "siemens-SADP", "dateUpdated": "2026-11-10T12:49:43.797Z" }, "affected": [ { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)", "versions": [ { "status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)", "versions": [ { "status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)", "versions": [ { "status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)", "versions": [ { "status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "versions": [ { "status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" } ], "references": [ { "url": "https://cert-portal.siemens.com/productcert/html/ssa-457936.html" } ] } ] } }