CVE-2026-85243: CWE-354 Improper Validation of Integrity Check Value in Apache Software Foundation Apache Camel

The vulnerability in Apache Camel Crypto PGP component arises from unmarshal() verifying the modification detection code only for OpenPGP symmetrically encrypted integrity protected data packets. Older symmetrically encrypted data packets do not carry this code, and OpenPGP's CFB mode is malleable without it, allowing messages using these packets to bypass integrity checks. Since the packet type is chosen by the message producer, an attacker or sender can decide whether integrity protection is applied, effectively allowing tampering without detection. The existing integrity option only governs marshalling and has no counterpart on the decrypt side, so deployments could not enforce integrity protection on accepted messages. The fix in Apache Camel 4.18.5, 4.22.1, and 4.23.0 adds a requireIntegrityProtection option defaulting to true, rejecting messages without integrity protection. For environments unable to upgrade immediately, it is recommended to reject messages lacking integrity protection before processing or set requireIntegrityProtection=false and treat such messages as unauthenticated.

This vulnerability allows an attacker or any entity able to modify messages in transit to bypass integrity checks by choosing or rewriting the message to use an older symmetrically encrypted data packet that lacks modification detection. This can lead to undetected message tampering, compromising message integrity without affecting confidentiality or availability. There is no indication of confidentiality or availability impact. The CVSS score is 5.9 (medium severity) reflecting the integrity impact with network attack vector and high attack complexity.

Upgrade Apache Camel to version 4.18.5 if using the 4.18.x LTS stream, to 4.22.1 if using the 4.22.x LTS stream, or to 4.23.0 or later. These versions introduce the requireIntegrityProtection option, which defaults to true and rejects messages lacking integrity protection. For deployments unable to upgrade immediately, implement message rejection for packets without integrity protection before they reach the data format processing stage. If interoperability with legacy senders is required, set requireIntegrityProtection=false after upgrading and treat decrypted content as unauthenticated. No other vendor advisories or patches are indicated.