{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-75806", "assignerOrgId": "3a12439a-ef3a-4c79-92e6-6081a721f1e5", "state": "PUBLISHED", "assignerShortName": "openssl", "dateReserved": "2026-08-18T09:34:32.659Z", "datePublished": "2026-09-29T15:32:21.457Z", "dateUpdated": "2026-11-10T12:49:45.393Z" }, "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" }, { "lessThan": "1.1.1zj", "status": "affected", "version": "1.1.1", "versionType": "custom" } ] } ], "credits": [ { "lang": "en", "type": "reporter", "value": "Mounir Idrassi" }, { "lang": "en", "type": "remediation developer", "value": "Mounir Idrassi" } ], "datePublic": "2026-09-29T14:21:57.000Z", "descriptions": [ { "lang": "en", "supportingMedia": [ { "base64": false, "type": "text/html", "value": "Issue summary: An established DTLS 1.2 association using an AEAD cipher suite
can be terminated by a single unauthenticated datagram whose encrypted
fragment is shorter than the mandatory explicit IV and authentication tag
overhead.

Impact summary: An attacker who can send a datagram that is routed to an
existing DTLS 1.2 association can tear that association down without knowing
any key material. This is a Denial of Service limited to the targeted
association. There is no memory safety or confidentiality impact.

CWE: CWE-1284: Improper Validation of Specified Quantity in Input

Description: In TLS 1.2 and DTLS 1.2 every record protected by an AEAD cipher
suite carries an explicit IV followed by the ciphertext and an authentication
tag. When decrypting such a record the record layer passed the record length to
the cipher implementation before checking that the record was long enough to
contain the explicit IV and the tag. For a record shorter than that overhead the
cipher implementation rejected the impossible length, and the record layer
treated this as an internal failure and raised a fatal internal_error alert
instead of treating the record as one that failed authentication.

In TLS 1.2 the same record causes a fatal internal_error alert instead of the
expected bad_record_mac alert. Since any undecryptable record already
terminates a TLS connection, this is a protocol conformance issue rather than
a security issue in TLS.

The fix validates the record length against the explicit IV and tag length
before any AEAD processing, so that TLS reports bad_record_mac and DTLS
silently discards the record.

FIPS impact: no
The affected code is outside the FIPS module boundary." } ], "value": "Issue summary: An established DTLS 1.2 association using an AEAD cipher suite\ncan be terminated by a single unauthenticated datagram whose encrypted\nfragment is shorter than the mandatory explicit IV and authentication tag\noverhead.\n\nImpact summary: An attacker who can send a datagram that is routed to an\nexisting DTLS 1.2 association can tear that association down without knowing\nany key material. This is a Denial of Service limited to the targeted\nassociation. There is no memory safety or confidentiality impact.\n\nCWE: CWE-1284: Improper Validation of Specified Quantity in Input\n\nDescription: In TLS 1.2 and DTLS 1.2 every record protected by an AEAD cipher\nsuite carries an explicit IV followed by the ciphertext and an authentication\ntag. When decrypting such a record the record layer passed the record length to\nthe cipher implementation before checking that the record was long enough to\ncontain the explicit IV and the tag. For a record shorter than that overhead the\ncipher implementation rejected the impossible length, and the record layer\ntreated this as an internal failure and raised a fatal internal_error alert\ninstead of treating the record as one that failed authentication.\n\nIn TLS 1.2 the same record causes a fatal internal_error alert instead of the\nexpected bad_record_mac alert. Since any undecryptable record already\nterminates a TLS connection, this is a protocol conformance issue rather than\na security issue in TLS.\n\nThe fix validates the record length against the explicit IV and tag length\nbefore any AEAD processing, so that TLS reports bad_record_mac and DTLS\nsilently discards the record.\n\nFIPS impact: no\nThe affected code is outside the FIPS module boundary." } ], "metrics": [ { "format": "other", "other": { "content": { "text": "Low" }, "type": "https://openssl-library.org/policies/general/security-policy/" } } ], "problemTypes": [ { "descriptions": [ { "cweId": "CWE-1284", "description": "CWE-1284 Improper Validation of Specified Quantity in Input", "lang": "en", "type": "CWE" } ] } ], "providerMetadata": { "orgId": "3a12439a-ef3a-4c79-92e6-6081a721f1e5", "shortName": "openssl", "dateUpdated": "2026-09-29T15:32:21.457Z" }, "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/04728a289a823e68137f88da016cb9ede307217d" }, { "name": "3.6.5 git commit", "tags": [ "patch" ], "url": "https://github.com/openssl/openssl/commit/050b275cd671a6eed1d6457642d41a5a77aab972" }, { "name": "3.5.9 git commit", "tags": [ "patch" ], "url": "https://github.com/openssl/openssl/commit/3a4589d015a9049d47b66f186cf50a8711343a1d" }, { "name": "3.4.8 git commit", "tags": [ "patch" ], "url": "https://github.com/openssl/openssl/commit/5af82fefbaf2b5fec2fc0e1d87f112844902f01d" } ], "source": { "discovery": "UNKNOWN" }, "title": "Unauthenticated and Undersized DTLS 1.2 AEAD Record Causes DoS", "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": "2026-09-29T16:52:47.298458Z", "id": "CVE-2026-75806", "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": "2026-09-29T16:53:23.785Z" } }, { "x_adpType": "supplier", "providerMetadata": { "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "shortName": "siemens-SADP", "dateUpdated": "2026-11-10T12:49:45.393Z" }, "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" } ] } ] } }