CVE-2026-45741 is a high-severity (CVSS 7.5) CWE-184 vulnerability in github.com/gotenberg/gotenberg/v8. O3 Security confirms whether CVE-2026-45741 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Gotenberg: SSRF deny-list bypass in IsPublicIP via IPv6 6to4 / NAT64 / site-local prefixes
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-45741.
Real-World Exposure
github.com/gotenberg/gotenberg/v8Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/gotenberg/gotenberg/v8 | all versions | No fix |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/gotenberg/gotenberg/v8. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of github.com/gotenberg/gotenberg/v8 has shipped for CVE-2026-45741 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-45741 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-45741. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-45741 in your dependencies?
O3 detects CVE-2026-45741 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.