Apache Camel camel-as2: Server-Side Request Forgery via asynchronous MDN address
Summary
The camel-as2 component of Apache Camel uses the asynchronous Message Disposition Notification (MDN) delivery address supplied by the AS2 sender without restriction. A remote trading partner can therefore make the receiver connect to arbitrary hosts, including internal systems not reachable from the internet. If MDN delivery credentials are configured, they are sent to the attacker-chosen host, which can disclose them. No authentication is required beyond the ability to send AS2 messages to the receiver.
Affected
- Apache Camel 4.0.0 to before 4.18.5
- Apache Camel 4.19.0 to before 4.22.1
- Camel 4.14.x (end of life, not fixed; move to 4.18.5 or later)
Fixed in
- Apache Camel 4.18.5 (4.18.x stream)
- Apache Camel 4.22.1 (4.22.x stream)
- Apache Camel 4.23.0
Workaround
- For deployments that cannot upgrade immediately, restrict outbound connectivity from the AS2 receiver to the partner endpoints that legitimately receive MDNs.
- Do not attach MDN credentials that are valid for hosts other than those partners.
- Configure the asyncMdnAllowedHosts option after upgrading; its behaviour when unset should be verified before relying on it.
Exploitation
- CISA SSVC (Vulnrichment): Exploitation none, automatable yes, technical impact partial.
- No evidence of exploitation in the wild found; the CISA KEV catalog was not checked.
- A public proof-of-concept reproducer is reported to exist.
Our recommendation
- Inventory Camel versions and camel-as2 usage, including Spring Boot, Quarkus and Red Hat Fuse builds.
- Upgrade to 4.18.5, 4.22.1 or 4.23.0 as appropriate.
- Limit outbound traffic of the AS2 receiver to known partner endpoints and remove credentials valid for other hosts.
- Check whether the AS2 endpoint is internet-reachable and review logs for unusual MDN destinations.
- Patch together with CVE-2026-85296 (camel-as2, receipt signature issue).
Public exploits
Links to third-party sites, not checked by us – exploit code can contain malware. Only use it in isolated test environments.
- Proof of concept on GitHub (1 repositories)
oscerd/CVE-2026-80344
Research sources
- Apache Camel security advisory CVE-2026-80344 camel.apache.org
- Pull Request #25637 (fix on main) github.com
- Pull Request #25763 (camel-4.22.x backport) github.com
- Pull Request #25764 (camel-4.18.x backport) github.com
- CAMEL-24417 Jira issue issues.apache.org
- Apache Camel security advisories 4.23.0 blog camel.apache.org
- OpenCVE entry CVE-2026-80344 app.opencve.io
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 1 Nov 2026, 15:48.
Original description (NVD)
Server-Side Request Forgery (SSRF) vulnerability in Apache Camel AS2 component. This issue affects Apache Camel: from 4.0.0 before 4.18.5, from 4.19.0 before 4.22.1. In the AS2 protocol the sender of a message may request that the Message Disposition Notification be returned asynchronously to an address the sender supplies. camel-as2 took that address from the inbound message and used it as the destination for the outgoing receipt without constraining it to anything the deployment had configured. A remote partner therefore chose the host the Camel instance would connect to when delivering the MDN. That gives server-side request forgery from the position of the AS2 receiver, including reaching hosts that are only routable from inside the deployment's network, and where the outbound connection carries credentials configured for MDN delivery those credentials are presented to the attacker-chosen destination. Upgrade to Apache Camel 4.23.0, which fixes the issue. Users on the 4.18.x LTS releases stream should upgrade to 4.18.5. Users on the 4.22.x LTS releases stream should upgrade to 4.22.1. The asynchronous MDN destination is now constrained rather than taken verbatim from the inbound message. For deployments that cannot upgrade immediately, restrict outbound connectivity from the AS2 receiver to the partner endpoints it legitimately delivers receipts to, and do not attach credentials to MDN delivery that are valid for any host other than those partners.
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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