# Gotenberg has Chromium deny-list bypass via case-insensitive URL scheme (bypass of GHSA-rh2x-ccvw-q7r3)

Advisory record · `GHSA-jjwv-57xh-xr6r`

- **Identifiers:** `GHSA-jjwv-57xh-xr6r` · `CVE-2026-27018` · `GO-2026-4905`
- **State:** Confirmed
- **Severity:** CVSS 7.8 High
- **Critical:** No
- **Weakness (CWE):** [CWE-22](https://cwe.mitre.org/data/definitions/22.html) · [CWE-918](https://cwe.mitre.org/data/definitions/918.html)
- **Tags:** [Path traversal](https://agentprime.io/advisories/tag/path-traversal.md) · [Server-side request forgery (SSRF)](https://agentprime.io/advisories/tag/ssrf.md)
- **Published:** 30 Mar 2026
- **Updated:** 8 Jul 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 30 Mar 2026, 16:16 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `github.com/gotenberg/gotenberg/v8` (Go): affected `<8.29.0`; fixed in `8.29.0`
- `github.com/gotenberg/gotenberg/v7` (Go): affected `<=7.10.2`; no fixed version yet

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> Gotenberg's Chromium deny-list can be bypassed with uppercase or mixed-case URL schemes, affecting github.com/gotenberg/gotenberg/v8 before 8.29.0 and github.com/gotenberg/gotenberg/v7 up to 7.10.2. An unauthenticated attacker who can reach the service can read files from the container. Upgrade the v8 module to 8.29.0; no fixed version is listed for v7.

Written 6 Nov 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 7.8 High, CVSS 4.0: `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:P`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.017, the 77th percentile, on 15 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 15:05 UTC: First seen by agentprime
- 31 Oct 2026, 15:05 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-jjwv-57xh-xr6r)

## Sources

- [GitHub Advisory Database: GHSA-jjwv-57xh-xr6r](https://github.com/advisories/GHSA-jjwv-57xh-xr6r)
- [OSV: GHSA-jjwv-57xh-xr6r](https://osv.dev/vulnerability/GHSA-jjwv-57xh-xr6r)
- <https://github.com/gotenberg/gotenberg/security/advisories/GHSA-jjwv-57xh-xr6r>
- <https://github.com/gotenberg/gotenberg/security/advisories/GHSA-rh2x-ccvw-q7r3>
- <https://nvd.nist.gov/vuln/detail/CVE-2026-27018>
- <https://github.com/gotenberg/gotenberg/commit/06b2b2e10c52b58135edbfe82e94d599eb0c5a11>
- <https://github.com/gotenberg/gotenberg/commit/8625a4e899eb75e6fcf46d28394334c7fd79fff5>
- <https://github.com/gotenberg/gotenberg>
- <https://github.com/gotenberg/gotenberg/releases/tag/v8.29.0>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-jjwv-57xh-xr6r>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-jjwv-57xh-xr6r/>. Everything for agents: <https://agentprime.io/llms.txt>.