CVE-2026-33454: Apache Camel's Camel-Mail component is vulnerable to Camel message header injection

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 1.0%, percentile 63: FIRST’s model estimates a 1.0% chance of exploitation activity in the next 30 days, higher than 63% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes org.apache.camel:camel-mail (Maven) >= 3.0.0, < 4.14.6, fixed in 4.14.6; org.apache.camel:camel-mail (Maven) >= 4.15.0, < 4.18.1, fixed in 4.18.1. Check your lockfile, including transitive dependencies.

What it is

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. This is the same pattern that was previously addressed in camel-undertow (CVE-2025-30177) and the broader incoming-header filter (CVE-2025-27636 and CVE-2025-29891). This issue affects Apache Camel: from 3.0.0 before 4.14.6, from 4.15.0 before 4.18.1. 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.

From the GitHub advisory

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. This is the same pattern that was previously addressed in camel-undertow (CVE-2025-30177) and the broader incoming-header filter (CVE-2025-27636 and CVE-2025-29891).

This issue affects Apache Camel: from 3.0.0 before 4.14.6, from 4.15.0 before 4.18.1.

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.

Weakness type: CWE-502, CWE-1173.

Product: org.apache.camel:camel-mail (Maven) · Assigned by: apache · Published: 2026-04-27

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: none
• Scope: unchanged

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable yes, technical impact partial.
• FIRST EPSS (model of 2026-10-21): 1.03% probability of exploitation activity in the next 30 days; percentile 63.

Timeline

• 2026-04-27 — CVE record published by apache
• 2026-04-27 — GitHub-reviewed advisory GHSA-2vqf-x7g4-7c2g published (critical)
• 2026-07-15 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vendor and project advisories, patches

1. camel.apache.org camel.apache.org
2. access.redhat.com access.redhat.com
3. access.redhat.com access.redhat.com

Vulnerability records

1. GitHub Advisory GHSA-2vqf-x7g4-7c2g github.com
2. CVE.org record CVE-2026-33454 cve.org
3. NVD entry CVE-2026-33454 nvd.nist.gov

Other references from the CVE record and advisory

1. access.redhat.com access.redhat.com
2. RHBZ#2463181 bugzilla.redhat.com
3. security.access.redhat.com security.access.redhat.com
4. github.com github.com
5. github.com github.com
6. github.com github.com
7. github.com github.com
8. github.com github.com
9. github.com github.com
10. github.com github.com
11. github.com github.com
12. github.com github.com
13. github.com github.com
14. github.com github.com
15. github.com github.com
16. github.com github.com
17. issues.apache.org issues.apache.org

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