CVE-2026-33454

Critical [CVE-2025-27636 +3] Apache Camel: Inbound Header Filter Missing in MailHeaderFilterStrategy Allows Remote Code Execution via MIME Header Injection (CVE-2025-30177 Variant)

CVE-2026-33454Source published Apr 27, 2026Source updated Jul 15, 2026

This bulletin covers 4 CVEs. The products, versions, score and guidance below describe the bulletin; check its source for applicability to this specific CVE.

The Camel-Mail component is vulnerable to Camel message header injection. The custom header filter strategy used by the component (MailHeaderFilterStrategy) only filters the 'out' direction via setOutFilterStartsWith, while it does not configure the 'in' direction via setInFilterStartsWith. As a result, when a Camel application consumes mail through camel-mail (for example via from(\"imap://...\") or from(\"pop3://...\")) the inbound filter check is skipped and Camel-prefixed MIME headers are mapped unfiltered into the Exchange. An attacker who can deliver an email to a mailbox monitored by such a consumer can inject Camel-specific headers that, for some Camel components downstream of the mail consumer (such as camel-bean, camel-exec, or camel-sql), can alter the behaviour of the route.…

Affected products in this advisory

• Apache Camel

Source-reported affected versions

• Apache Camel 3.0.0 before 4.14.6
• Apache Camel 4.15.0 before 4.18.1

Source-reported fixed versions

• 4.14.6
• 4.18.1

Mitigation guidance

• The custom header filter strategy used by the component (MailHeaderFilterStrategy) only filters the 'out' direction via setOutFilterStartsWith, while it does not configure the 'in' direction via setInFilterStartsWith.
• Users are recommended to upgrade to version 4.19.0, which fixes the issue.
• If users are on the 4.18.x LTS releases stream, then they are suggested to upgrade to 4.18.1.
• If users are on the 4.14.x LTS releases stream, then they are suggested to upgrade to 4.14.6.

Critical [CVE-2026-33454] Altered application behavior via header injection

CVE-2026-33454Source published Apr 27, 2026

Altered application behavior via header injection. Red Hat rates this critical (CVSS 9.4). Weakness: CWE-1173. Affected package(s): camel-mail. Resolved in Red Hat advisory RHSA-2026:19835 — update the affected packages (`sudo dnf update`).

Affected products in this advisory

• Red Hat build of Apache Camel 4 for Quarkus 3

Source-reported affected versions

• camel-mail

Source-reported fixed versions

• RHSA-2026:19835

Mitigation guidance

• Update the affected package(s) to the fixed version shipped in RHSA-2026:19835 (`sudo dnf update` / `yum update`).