CVE-2026-42593

Published May 14, 2026

Last updated 13 days ago

CVSS medium 5.3

Overview

Description
Gotenberg is a Docker-powered stateless API for PDF files. Prior to 8.32.0, pdfengines/merge, pdfengines/split, libreoffice/convert, chromium/convert/url, chromium/convert/html, and chromium/convert/markdown accept stampSource=pdf + stampExpression=/path and watermarkSource=pdf + watermarkExpression=/path from anonymous callers. The dedicated stamp/watermark routes require an uploaded file when the source type is image or pdf; these six routes only overwrite the expression when a file is uploaded, leaving the user-controlled path intact when no file is attached. pdfcpu opens the path and composites its pages onto the output PDF, which returns to the caller. An attacker reads any PDF the Gotenberg process can access on the container filesystem. This vulnerability is fixed in 8.32.0.
Source
security-advisories@github.com
NVD status
Analyzed
Products
gotenberg

Risk scores

CVSS 3.1

Type
Secondary
Base score
5.3
Impact score
1.4
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Severity
MEDIUM

Weaknesses

security-advisories@github.com
CWE-22

Social media

Hype score
Not currently trending

Configurations

Related CVEs

  1. Gotenberg is a Docker-powered stateless API for PDF files. Prior to 8.32.0, the /forms/chromium/convert/url and /forms/chromium/screenshot/url routes accept url=file:///tmp/... from anonymous callers. The default Chromium deny-list intentionally exempts file:///tmp/ so HTML/Markdown routes can load their own request-local assets, and those routes apply a per-request AllowedFilePrefixes guard to scope the read. The URL routes never set AllowedFilePrefixes, so the scope guard silently skips. Alice enumerates /tmp/, walks Gotenberg's per-request working directories, and reads the raw source files of other in-flight conversions as rendered PDF output. This vulnerability is fixed in 8.32.0.•CVE-2026-42597
  2. Gotenberg is a Docker-powered stateless API for PDF files. Prior to 8.31.0, the default deny-lists used by Gotenberg's downloadFrom feature and webhook feature are bypassable. Because the filter is regex-based and case-sensitive, an unauthenticated attacker can supply URLs such as http://[::ffff:127.0.0.1]:... and reach loopback or private HTTP services that the default deny-list is intended to block. This crosses a real security boundary because an external caller can force the server to make outbound requests to internal-only targets. This vulnerability is fixed in 8.31.0.•CVE-2026-42596
  3. Gotenberg is a Docker-powered stateless API for PDF files. Prior to 8.32.0, Gotenberg's Chromium URL-to-PDF endpoint (/forms/chromium/convert/url) has no default protection against HTTP/HTTPS-based SSRF. The default deny-list regex only blocks file:// URIs. An unauthenticated attacker can point Chromium at any internal IP — including loopback, RFC 1918 ranges, and cloud metadata endpoints — and receive the response rendered as a PDF. Additionally, even when operators configure a custom deny-list, the protection is bypassed via HTTP redirects. Gotenberg's Chromium instance follows 302 redirects from an attacker-controlled external URL to internal targets without re-validating the redirect destination against the deny-list. This vulnerability is fixed in 8.32.0.•CVE-2026-42595
  4. Gotenberg is a Docker-powered stateless API for PDF files. Prior to 8.32.0, the webhook middleware spawns a goroutine that holds a reference to the request's echo.Context after the synchronous handler returns ErrAsyncProcess and Echo recycles the context back to its sync.Pool. When a concurrent request claims the recycled context, c.Reset() clears the store. If the webhook goroutine reaches hardTimeoutMiddleware at that moment, an unchecked type assertion on a nil store entry panics outside any recover() scope, crashing the Gotenberg process. Any anonymous caller reaches the webhook path (default webhook-deny-list filters only the webhook destination, not the submitter). A single-source stress of ~24 webhook requests plus ~60 GET /version requests crashes the process in about two seconds. This vulnerability is fixed in 8.32.0.•CVE-2026-42594
  5. Gotenberg is a Docker-powered stateless API for PDF files. Prior to 8.32.0, FilterOutboundURL resolves the hostname, checks the resolved IPs against the private-address deny-list, and returns only the error. It discards the resolved addresses. Chromium later performs its own DNS resolution when it navigates to the URL. An attacker who controls DNS for a hostname with a short TTL returns a public IP on the first query (Gotenberg allows) and a private IP on the second query (Chromium connects to the attacker-chosen internal address). The CDP Fetch.requestPaused handler re-checks the URL but runs its own DNS resolution, leaving a timing window before Chromium's actual TCP connect. The rendered internal service response returns to the caller as a PDF. This vulnerability is fixed in 8.32.0.•CVE-2026-42592

References

Sources include official advisories and independent security research.