CVE-2026-45742 Gotenberg: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

What is CVE-2026-45742?

CVE-2026-45742 is a high-severity vulnerability in gotenberg, published on 19 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official 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.

Weakness: CWE-362

Which versions are affected by CVE-2026-45742?

4 open source packages ship an affected version, including github.com/gotenberg/gotenberg/v8 and github.com/gotenberg/gotenberg/v7.

How do I fix CVE-2026-45742?

Upgrade github.com/gotenberg/gotenberg/v8 to 8.33.0 or later.

Is CVE-2026-45742 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45742 exists.

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-vp73-vjw8-8f32, GO-2026-5669.