CyberSecBulletin
CVE-2026-45741NVD status: Deferred

gotenberg: Incomplete List of Disallowed Inputs

CVE-2026-45741 is a high-severity incomplete list of disallowed inputs vulnerability in gotenberg, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected gotenberg versions: < 8.33.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.37% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of gotenberg you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Gotenberggotenberg< 8.33.0Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
LowLimited modification of data is possible.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N. Scored by CNA (github.com).

Official description

Gotenberg is a Docker-powered stateless API for PDF files. In 8.32.0 and earlier, the IsPublicIP function in pkg/gotenberg/outbound.go does not reject the 2002::/16 6to4 prefix, the 64:ff9b::/96 and 64:ff9b:1::/48 NAT64 prefixes, the fec0::/10 deprecated site-local prefix, Teredo, and other transition prefixes that can embed or route to non-public IPv4 destinations. The addr.Unmap operation only handles IPv4-mapped IPv6 addresses, so a crafted DNS AAAA record can cause the outbound HTTP client to treat an address wrapping an internal destination such as 169.254.169.254 as public. An unauthenticated attacker can use a conversion route with WithDenyPrivateIPs enabled to reach cloud metadata services, and the Chromium URL conversion route can return the internal response as a PDF, potentially exposing cloud credentials. Exploitation requires a deployment whose host routes the relevant IPv6 prefix, such as a dual-stack or NAT64-enabled environment. This issue is fixed in version 8.33.0.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Incomplete List of Disallowed Inputs

The product implements a protection mechanism that relies on a list of inputs (or properties of inputs) that are not allowed by policy or otherwise require other action to neutralize before additional processing takes place, but the list is incomplete.

How developers prevent this class of flaw

  • Do not rely exclusively on detecting disallowed inputs. There are too many variants to encode a character, especially when different environments are used, so there is a high likelihood of missing some variants. Only use detection of disallowed inputs as a mechanism for detecting suspicious activity. Ensure that you are using other protection mechanisms that only identify good input - such as lists of allowed inputs - and ensure that you are properly encoding your outputs.

More Incomplete List of Disallowed Inputs vulnerabilities (CWE-184)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in gotenberg

All gotenberg vulnerabilities

Recent Incomplete List of Disallowed Inputs vulnerabilities

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