Secuno
ENNL
Book demo

CVE-2026-39383

Thecodingmachine Gotenberg server-side request forgery (SSRF)

7.2 HIGHPublic exploitEPSS 0.31%
  1. Published5 May 2026

Description

Gotenberg is an API-based document conversion tool. In version 8.29.1, an unauthenticated attacker with network access can force the server to make outbound HTTP POST requests to arbitrary internal or external destinations by supplying a crafted URL in the Gotenberg-Webhook-Url request header. The FilterDeadline function in filter.go is intended to gate outbound URLs, but when both the allow-list and deny-list are empty (the default configuration), it returns nil unconditionally and permits any URL. This is a blind SSRF: Gotenberg POSTs the converted document to the webhook URL and only checks whether the response status code is an error, but never returns the target's response body to the attacker. An attacker can use this to probe internal network infrastructure by observing whether the error callback is invoked, force POST requests against internal services that perform side effects, and confirm reachability of cloud metadata endpoints. The retryable HTTP client issues up to 4 automatic retries per request, amplifying each probe. This issue has been fixed in version 8.31.0. As a workaround, configure the GOTENBERG_API_WEBHOOK_ALLOW_LIST environment variable to restrict webhook URLs to known receivers, or set GOTENBERG_API_WEBHOOK_DENY_LIST to block RFC-1918 and link-local address ranges.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

Affected products

Thecodingmachine Gotenberg≥ 8.29.1 < 8.31.0

Remediation

Fixed in
Thecodingmachine Gotenberg≥ 8.31.0

References

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

CVE-2026-8911110.0
The SAP Cloud SDK for Python contains an OAuth2 SSRF vulnerability affecting…
CVE-2026-571438.8
PraisonAI is a multi-agent teams system. Prior to praisonaiagents 1.6.62,…
CVE-2026-1092388.6
Crawl4AI 0.7.0 before 0.9.4 contains a server-side request forgery vulnerability that…
CVE-2026-859528.5
Affected Linux-based Progress MarkLogic Server 12.x releases before 12.1.0 and 11.x…
CVE-2026-859518.5
Progress MarkLogic Server 12.x releases before 12.1.0 and 11.x releases before 11.3.7…
CVE-2026-694359.6
Missing authorization in Azure SRE Agent allows an authorized attacker to elevate…

Frequently asked

Is CVE-2026-39383 being actively exploited?

CVE-2026-39383 is not in the CISA KEV catalog. A public exploit reference exists, so treat it as exploitable. Its EPSS exploit probability is 0.31%.

How severe is CVE-2026-39383?

CVE-2026-39383 has a CVSS 3.1 base score of 7.2, rated high. EPSS estimates a 0.31% probability of exploitation.

Which products are affected by CVE-2026-39383?

Affected products include Thecodingmachine Gotenberg.

How do I fix CVE-2026-39383?

Upgrade affected software to a fixed version, for example Thecodingmachine Gotenberg 8.31.0 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-39383 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation worksBook a demo

Get Patch this first every Monday

Five vulnerabilities that matter this week, ranked on real exploitation. Plain language, one email, no spam.

You can unsubscribe with one click from every issue. We handle your details as described in our privacy policy.

Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.