CVE-2026-45742
Received Received - Intake

Race Condition in Gotenberg PDF Conversion Service

Publication date: 2026-08-19

Last updated on: 2026-08-19

Assigner: GitHub, Inc.

Description
Gotenberg is a Docker-powered stateless API for PDF files. From 8.10.0 until 8.33.0, the newContext function in pkg/modules/api/context.go starts one errgroup.Go goroutine for each multipart downloadFrom entry and allows those goroutines to concurrently write to the shared ctx.files, ctx.diskToOriginal, and ctx.filesByField maps and slices. Go maps and slices are not safe for concurrent mutation, so a crafted multipart request containing many downloadFrom entries can trigger a data race and terminate the process with a fatal concurrent map writes runtime error. The default configuration enables downloadFrom and disables authentication, allowing an unauthenticated remote attacker to crash an exposed conversion service and cause a denial of service. This issue is fixed in version 8.33.0.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-08-19
Last Modified
2026-08-19
Generated
2026-08-19
AI Q&A
2026-08-19
EPSS Evaluated
N/A
NVD
CVE-2026-45742
EUVD
EUVD-2026-62425

Affected Vendors & Products

Showing 2 associated CPEs
Vendor Product Version / Range
gotenberg gotenberg From 8.10.0 (inc) to 8.32.0 (inc)
gotenberg gotenberg 8.33.0

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-362 The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

This vulnerability is a race condition in Gotenberg versions 8.10.0 to 8.32.0. When processing multipart requests with the downloadFrom feature, multiple goroutines concurrently write to shared maps without synchronization. This causes a fatal error 'concurrent map writes' and crashes the application.

Detection Guidance

Monitor for crashes with 'fatal concurrent map writes' errors in Gotenberg logs. Use Go's race detector by running Gotenberg with the -race flag to detect concurrent map access during operation.

Impact Analysis

An unauthenticated remote attacker can exploit this to crash the Gotenberg service, causing a denial of service. The attack only affects availability, not confidentiality or integrity. The default configuration allows this attack if downloadFrom is enabled and authentication is disabled.

Compliance Impact

This vulnerability primarily impacts availability by causing denial-of-service through process crashes, which does not directly affect data confidentiality or integrity required by standards like GDPR or HIPAA. However, prolonged downtime could disrupt services handling sensitive data, potentially leading to compliance issues if systems fail to meet availability requirements.

Mitigation Strategies

Upgrade to Gotenberg version 8.33.0 or later to patch the race condition. If upgrading is not immediately possible, disable the downloadFrom feature in the configuration or enable authentication to restrict access.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-45742. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart