CVE-2026-42766
Impact summary: This NULL pointer dereference leads to an application crash and a Denial of Service.
Does this matter?
Lower severity and a low EPSS score (1.06%). Track it; it rarely justifies an emergency change on its own.
Description
Issue summary: A specially crafted password-encrypted CMS message can trigger a NULL pointer dereference during CMS decryption. Impact summary: This NULL pointer dereference leads to an application crash and a Denial of Service. The CMS PasswordRecipientInfo.keyDerivationAlgorithm field is defined as OPTIONAL in the ASN.1 specification and may therefore be absent in specially crafted inputs. During the password-based CMS decryption the OpenSSL CMS implementation dereferences this field without first checking whether it was present. An attacker who supplies such a CMS message to an application performing password-based CMS decryption can trigger an application crash, leading to a Denial of Service. Applications that process password-encrypted CMS messages may be affected. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.
- CVSS 3.1
- 5.9 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 1.06% probability · 63th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Affected
- openssl/openssl
- Source
- openssl-security@openssl.org
References
- https://github.com/openssl/openssl/commit/056d06c1918fafbb98c1c85a02e4c47cc4e199cePatch
- https://github.com/openssl/openssl/commit/12bc26ffb3a2be728c9b86e1cae277de5b33dfa4Patch
- https://github.com/openssl/openssl/commit/3ff64913615d648cfbb6a6f1cf5529ae7ea829d7Patch
- https://github.com/openssl/openssl/commit/ab52d88cb5374876d59aee3c91f9e4ccce2b7ce4Patch
- https://github.com/openssl/openssl/commit/da26f368732b83e40e9d356fe61c3d3aaab6d2e8Patch
- https://openssl-library.org/news/secadv/20260609.txtVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.