Cyber Resilience

CVE-2026-42597

SSRF in Thecodingmachine Gotenberg ≤ 8.32.0

Published
14 May 2026
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 5.9
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0025 17th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-42597 is a medium-severity External Control of File Name or Path (CWE-73) vulnerability in Thecodingmachine Gotenberg. Its CVSS base score is 5.9 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 17th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

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…

more

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.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
Why these techniques?

Public-facing web API routes directly exploitable for unauthorized local file reads in /tmp (T1190 initial access + T1005 data collection).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-42593Same product: Thecodingmachine Gotenberg
CVE-2026-27018Same product: Thecodingmachine Gotenberg
CVE-2026-42591Same product: Thecodingmachine Gotenberg
CVE-2026-42596Same product: Thecodingmachine Gotenberg
CVE-2026-42592Same product: Thecodingmachine Gotenberg
CVE-2026-40280Same product: Thecodingmachine Gotenberg
CVE-2026-42595Same product: Thecodingmachine Gotenberg
CVE-2026-39383Same product: Thecodingmachine Gotenberg
CVE-2026-40893Same product: Thecodingmachine Gotenberg
CVE-2026-42589Same product: Thecodingmachine Gotenberg

Affected Assets

thecodingmachine
gotenberg
≤ 8.32.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • SI-10 Information Input Validation
  • AC-4 Information Flow Enforcement
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V5.3.2
  • V1.3.6
  • V1.5.3
  • V10.4.7

Mitigating Controls (NIST 800-53 r5) AI

prevent

Enforces per-request AllowedFilePrefixes scoping on file:// URLs so that chromium URL routes cannot silently bypass the guard and read other users' working directories.

prevent

Validates incoming url parameters on /forms/chromium/*/url routes to reject file:///tmp/ (and similar) values that the Chromium allow-list intentionally exempts.

prevent

Enforces information-flow rules that restrict which external or file-scheme resources may be fetched by unauthenticated conversion requests.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 full match
prevents

Secure SDLC practices include input validation and path sanitization that eliminate this weakness.

PR.AA-05 mostly match
prevents

Least-privilege file authorization directly limits damage from externally controlled paths.

DE.CM-09 partial match
prevents

Runtime monitoring of web applications and services can detect anomalous outbound requests indicative of SSRF.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover and record SSRF flaws in web applications.

PR.IR-01 partial match
prevents

Network segmentation and egress controls can limit the damage from successful SSRF requests.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing can detect path-traversal issues but does not itself implement preventive controls.

prevents

Operational threat data describing SSRF campaigns can be used to tighten outbound-request allow-lists and detection rules before attackers exploit them.

prevents

Secure development lifecycle mandates input validation and path-handling controls that directly prevent external file/path manipulation.

prevents

Application security requirements explicitly call for controls against untrusted input influencing file operations.

prevents

Secure architecture principles discourage unsafe path construction but do not prescribe concrete file-name controls.

prevents

Secure coding standards require canonicalization, allow-listing, and bounds checks on file paths, directly eliminating CWE-73.

References