SimpleSAMLphp SAML2 has an XXE in parsing SAML messages

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

6.9 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:L · score source

EPSS

• CVE-2024-52806: 0.43% estimated exploitation activity in the next 30 days; percentile 37.54 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary When loading an (untrusted) XML document, for example the SAMLResponse, it's possible to induce an XXE. $options is defined as: https://github.com/simplesamlphp/saml2/blob/717c0adc4877ebd58428637e5626345e59fa0109/src/SAML2/DOMDocumentFactory.php#L41 including the DTDLoad option, which allows an attacker to read file contents from local file system OR internal network. While there is the NONET option, an attacker can simply bypass if by using PHP filters: php://filter/convert.base64-encode/resource=http://URL OR FILE From there an attacker can induce network connections and steal the targeted file OOB (haven't fully tested this). RCE may be possible with the php://expect or php://phar wrappers, but this hasn't been tested. Note: The mitigation here: https://github.com/simplesamlphp/saml2/blob/717c0adc4877ebd58428637e5626345e59fa0109/src/SAML2/DOMDocumentFactory.php#L63-L69 Comes too late, as the XML has already been loaded into a document. Mitigation: Remove the LIBXMLDTDLOAD…

Published by the source

2 Dec 2024, 17:25 UTC

Last modified by the source

13 Dec 2024, 20:39 UTC

Source last checked

26 Oct 2026, 14:29 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-pxm4-r5ph-q2m2

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# Patch Next advisory brief: CVE-2024-52806

Advisory: SimpleSAMLphp SAML2 has an XXE in parsing SAML messages
IDs: CVE-2024-52806, GHSA-pxm4-r5ph-q2m2
Record: https://patchnext.com/advisories/cve-2024-52806 (revision 1, source checked 26 Oct 2026, 14:29 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: simplesamlphp/saml2-legacy 4.6.14; simplesamlphp/saml2 4.6.14. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist simplesamlphp/saml2-legacy: affected < 4.6.14; fixed in 4.6.14
- Packagist simplesamlphp/saml2: affected < 4.6.14; fixed in 4.6.14

## Suggested inspection (read-only)
- Packagist simplesamlphp/saml2-legacy: check the installed version with your package manager.
- Packagist simplesamlphp/saml2: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on simplesamlphp/saml2-legacy, simplesamlphp/saml2.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-pxm4-r5ph-q2m2 (GitHub-reviewed advisory GHSA-pxm4-r5ph-q2m2 lists affected ranges: Packagist simplesamlphp/saml2 >=0 =0 <4.6.14)

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