{"cve":"CVE-2026-42766","nvd":{"published":"2026-06-09T17:17:07.970","modified":"2026-07-23T08:10:00.137","status":"Analyzed","description":"Issue summary: A specially crafted password-encrypted CMS message\ncan trigger a NULL pointer dereference during CMS decryption.\n\nImpact summary: This NULL pointer dereference leads to an application crash\nand a Denial of Service.\n\nThe CMS PasswordRecipientInfo.keyDerivationAlgorithm field is defined as\nOPTIONAL in the ASN.1 specification and may therefore be absent in specially\ncrafted inputs. During the password-based CMS decryption the OpenSSL\nCMS implementation dereferences this field without first checking whether it\nwas present.\n\nAn attacker who supplies such a CMS message to an application performing\npassword-based CMS decryption can trigger an application crash, leading to\na Denial of Service.\n\nApplications that process password-encrypted CMS messages may be affected.\n\nThe FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this\nissue, as the affected code is outside the OpenSSL FIPS module boundary.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":5.9},"cwes":["CWE-476"],"references":["https://github.com/openssl/openssl/commit/056d06c1918fafbb98c1c85a02e4c47cc4e199ce","https://github.com/openssl/openssl/commit/12bc26ffb3a2be728c9b86e1cae277de5b33dfa4","https://github.com/openssl/openssl/commit/3ff64913615d648cfbb6a6f1cf5529ae7ea829d7","https://github.com/openssl/openssl/commit/ab52d88cb5374876d59aee3c91f9e4ccce2b7ce4","https://github.com/openssl/openssl/commit/da26f368732b83e40e9d356fe61c3d3aaab6d2e8"],"products":["openssl:openssl"],"source":"nvd","synced_at":"2026-10-19T22:38:48.522727527+00:00"},"epss":{"cve":"CVE-2026-42766","score":0.0106,"percentile":0.64551,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}