CVE-2026-61855 Zammad: Invalid PGP Detached Signatures Reported as Good Signature on Inbound Mail
Attackers can spoof PGP signatures in inbound emails, misleading support agents into trusting unverified content.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-61855?
CVE-2026-61855 is a medium-severity vulnerability in zammad, published on 25 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Zammad is a web based open source helpdesk/customer support system. In 7.0.3 and 7.1.1, under certain conditions, Zammad's verification of inbound PGP-signed email can mark a message as carrying a valid ("Good") PGP signature from a registered sender key, even though the displayed message content is not actually covered by that signature. As a result, the inbound article may be stored with a successful signature status that does not reflect the authenticity of the shown content. This can mislead agents who rely on the signature indicator when assessing the trustworthiness of incoming mail. This issue is fixed in version 7.1.2.
Weakness: CWE-347
Which versions are affected by CVE-2026-61855?
How do I fix CVE-2026-61855?
No fix has been published for CVE-2026-61855 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-61855 being exploited?
There is no known exploitation of CVE-2026-61855 in the wild and no public exploit code.
Sources
Also known as GHSA-r957-vp26-563q.