CVE-2026-16027 Unauthenticated WebSocket-to-XAdES SSRF in Revenue Administration's E-Signature
Unauthenticated attackers can exploit a WebSocket-to-XAdES flaw to perform Server-Side Request Forgery, potentially accessing internal resources.
- 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-2026-16027?
CVE-2026-16027 is a medium-severity server-side request forgery vulnerability in Revenue Administration E-Signature, published on 7 Aug 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
Server-Side request forgery (SSRF) vulnerability in Revenue Administration Türkiye's E-Signature allows Server Side Request Forgery.
This issue affects Türkiye's E-Signature: from 2.4.4.0 before 2.5.1.0.
Weakness: CWE-918
Which versions are affected by CVE-2026-16027?
How do I fix CVE-2026-16027?
No fix has been published for CVE-2026-16027 yet. Limit exposure of the affected software until one is available.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-16027 being exploited?
There is no known exploitation of CVE-2026-16027 in the wild and no public exploit code.
Sources
Also known as GHSA-jxrw-hc36-36pw.