CVE-2026-42594 Gotenberg: Unauthenticated denial of service via echo.Context pool reuse in webhook async goroutine

What is CVE-2026-42594?

CVE-2026-42594 is a high-severity vulnerability in gotenberg, published on 14 May 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. 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.

Weakness: CWE-362

Which versions are affected by CVE-2026-42594?

4 open source packages ship an affected version, including github.com/gotenberg/gotenberg/v8 and github.com/gotenberg/gotenberg/v7. It affects 1 product.

Products include Thecodingmachine Gotenberg.

How do I fix CVE-2026-42594?

Upgrade github.com/gotenberg/gotenberg/v8 to 8.32.0 or later.

Is CVE-2026-42594 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42594 exists.

Other vulnerabilities in gotenberg

• CVE-2026-40281 Gotenberg vulnerable to argument injection via newlines in ExifTool metadata values Critical 10.0
• CVE-2026-42589 Gotenberg: Unauthenticated RCE via ExifTool Metadata Key Injection Critical 9.8
• CVE-2020-13450 Path traversal in n/a Critical 9.8
• CVE-2020-13451 Code injection in n/a Critical 9.8
• CVE-2020-13452 Privilege escalation in n/a Critical 9.8

Sources

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

Also known as GHSA-r33j-c622-r6qp, GO-2026-5605.