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CVE-2024-56324NVD status: Analyzed

gocd: Improper Restriction of XML External Entity Reference

CVE-2024-56324 is a high-severity improper restriction of XML external entity reference vulnerability in gocd, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected gocd versions: < 24.5.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.81% chance of exploitation within 30 days, higher than 57% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of gocd 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.

Affected products and versions

VendorProductAffected versionsFixed in
Gocdgocd< 24.5.0Not 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
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
LowPerformance or availability is reduced.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:L. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 4.02.1LowCNA (github.com)
CVSS 3.17.1HighNVD

Official description

GoCD is a continuous deliver server. GoCD versions prior to 24.4.0 can allow GoCD "group admins" to abuse ability to edit the raw XML configuration for groups they administer to trigger XML External Entity (XXE) injection on the GoCD server. Theoretically, the XXE vulnerability can result in additional attacks such as SSRF, information disclosure from the GoCD server, and directory traversal, although these additional attacks have not been explicitly demonstrated as exploitable. This issue is fixed in GoCD 24.5.0. Some workarounds are available. One may temporarily block access to `/go/*/pipelines/snippet` routes from an external reverse proxy or WAF if one's "group admin" users do not need the functionality to edit the XML of pipelines directly (rather than using the UI, or using a configuration repository). One may also prevent external access from one's GoCD server to arbitrary locations using some kind of environment egress control.

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

The underlying weakness: Improper Restriction of XML External Entity Reference

The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.

How developers prevent this class of flaw

  • Many XML parsers and validators can be configured to disable external entity expansion.

More Improper Restriction of XML External Entity Reference vulnerabilities (CWE-611)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in gocd

All gocd vulnerabilities

Recent Improper Restriction of XML External Entity Reference vulnerabilities

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