Open redirect in user_saml via RelayState parameter in Nextcloud User Saml

published 2024-01-18 2 y ago modified 2026-06-17 4 mo ago also EUVD-2024-19955

cvss: 3.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 39%
public exploits: 0; none known

Nextcloud User Saml is an app for authenticating Nextcloud users using SAML. In affected versions users can be given a link to the Nextcloud server and end up on a uncontrolled thirdparty server. It is recommended that the User Saml app is upgraded to version 5.1.5, 5.2.5, or 6.0.1. There are no known workarounds for this issue.

Patch / fix

fixed in 1 links 2

nextcloud sso_&_saml_authentication 5.1.5, 5.2.5

github.com/nextcloud/user_saml@b184304 commit
github.com/nextcloud/user_saml#788 pull request

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2024-22400 updated 2026-06-26

nextcloud: users can be given a link to the Nextcloud server and end up on a uncontrolled thirdparty server

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2 y ago (2024-01-19)

Exploit prediction

0.45% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	3.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N
NVD	3.1	6.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected products

nextcloud security-advisories

Classification

Weakness

CWE-601 URL Redirection to Untrusted Site

References

github.com /nextcloud/user_saml/pull/788
patch
github.com /nextcloud/user_saml/commit/b184304a476deeba36e92b70562d5de7c2f85f8a
patch
github.com /nextcloud/security-advisories/security/advisories/GHSA-622q-xhfr-xmv7
vendor-advisory
hackerone.com /reports/2263044
permissions-required, third-party-advisory

Sources

CVE List CVE-2024-22400
NVD CVE-2024-22400

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary