CVE-2026-45741 Gotenberg: SSRF deny-list bypass in IsPublicIP via IPv6 6to4 / NAT64 / site-local prefixes
An unauthenticated attacker can bypass SSRF protections via IPv6 transition prefixes to access internal cloud metadata and expose credentials.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-45741?
CVE-2026-45741 is a high-severity server-side request forgery vulnerability in gotenberg, published on 19 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Gotenberg is a Docker-powered stateless API for PDF files. In 8.32.0 and earlier, the IsPublicIP function in pkg/gotenberg/outbound.go does not reject the 2002::/16 6to4 prefix, the 64:ff9b::/96 and 64:ff9b:1::/48 NAT64 prefixes, the fec0::/10 deprecated site-local prefix, Teredo, and other transition prefixes that can embed or route to non-public IPv4 destinations. The addr.Unmap operation only handles IPv4-mapped IPv6 addresses, so a crafted DNS AAAA record can cause the outbound HTTP client to treat an address wrapping an internal destination such as 169.254.169.254 as public. An unauthenticated attacker can use a conversion route with WithDenyPrivateIPs enabled to reach cloud metadata services, and the Chromium URL conversion route can return the internal response as a PDF, potentially exposing cloud credentials. Exploitation requires a deployment whose host routes the relevant IPv6 prefix, such as a dual-stack or NAT64-enabled environment. This issue is fixed in version 8.33.0.
Which versions are affected by CVE-2026-45741?
4 open source packages ship an affected version, including github.com/gotenberg/gotenberg/v8 and github.com/gotenberg/gotenberg/v7.
| Package | Affected | Fixed in |
|---|---|---|
github.com/gotenberg/gotenberg/v8 Go | All versions | None |
github.com/gotenberg/gotenberg/v8 Go | All versions to 8.32.0 | None |
github.com/gotenberg/gotenberg/v8 Go | All versions to 8.32.0 | None |
github.com/gotenberg/gotenberg/v7 Go | All versions | None |
How do I fix CVE-2026-45741?
Upgrade to a fixed version.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-45741 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45741 exists.
Sources
Also known as GHSA-86m8-88fq-xfxp, GO-2026-5244.