Vulnerability · Published Sep 25, 2026 · Assigned by GitHub_M

CVE-2026-56734Zammad: Avatar Image URL Server-Side Request Forwarding

Medium 5.3

In plain English

A medium-severity server-side request forgery in zammad from zammad. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 34% of all known vulnerabilities).

Severity (CVSS 4.0)5.3Medium

Exploit odds (30 days)0.4%top 65.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Zammad is a web based open source helpdesk/customer support system. Prior to 7.0.2, during federated authentication (OAuth/OIDC/SAML), a profile image URL from the external identity provider is fetched without verifying the target address. An actor who controls their profile at a connected provider may cause the server to connect to internal network locations. Response timing and error patterns differ between reachable and unreachable targets, allowing internal service probing. Worker processes may be blocked for several seconds per request. Requires a configured external authentication provider where the actor can modify their profile image URL. This issue is fixed in version 7.0.2.

Affected products (as reported)

Vendor	Product	Versions
zammad	zammad	< 7.0.2

Weakness: CWE-918 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N

References

https://github.com/zammad/zammad/security/advisories/GHSA-q3cr-3wq3-29hx x_refsource_CONFIRM
https://github.com/zammad/zammad/commit/1fae97d92496a643ea1490fb17070881e4e091d5 x_refsource_MISC
https://github.com/zammad/zammad/releases/tag/7.0.2 x_refsource_MISC