CVE-2023-3550

Name: CVE-2023-3550
Creator: NVD / NIST
Published: 2023-09-25T16:15:14.347+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.3/10EPSS 1.15%

Last modified Jun 17, 2026

CVE-2023-3550 is a high-severity vulnerability rated 7.3/10 on the CVSS scale. Mediawiki v1.40.0 does not validate namespaces used in XML files. Therefore, if the instance administrator allows XML file uploads, a remote attacker with a low-privileged user account can use this exploit to become an administrator by sending a malicious link to the instance administrator.. EPSS estimates a 1.15% chance of exploitation in the next 30 days.

Description

Mediawiki v1.40.0 does not validate namespaces used in XML files. Therefore, if the instance administrator allows XML file uploads, a remote attacker with a low-privileged user account can use this exploit to become an administrator by sending a malicious link to the instance administrator.

Metrics

CVSS 3.1

7.3/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N

EPSS Probability

1.15%

62.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Mediawiki	Mediawiki	1.40.0
Debian	Debian Linux	10.0
Debian	Debian Linux	11.0

References

https://fluidattacks.com/advisories/blondie/Exploit, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/11/msg00027.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/FU2FGUXXK6TMV6R52VRECLC6XCSQQISY/
https://www.debian.org/security/2023/dsa-5520Third Party Advisory
https://www.mediawiki.org/wiki/MediaWiki/Product
https://fluidattacks.com/advisories/blondie/Exploit, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/11/msg00027.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/FU2FGUXXK6TMV6R52VRECLC6XCSQQISY/
https://www.debian.org/security/2023/dsa-5520Third Party Advisory
https://www.mediawiki.org/wiki/MediaWiki/Product

Timeline

Published: Sep 25, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-3550?

How severe is CVE-2023-3550?

CVE-2023-3550 has a CVSS score of 7.3/10 (HIGH severity). The EPSS model estimates a 1.15% probability of exploitation in the next 30 days.

How do I fix CVE-2023-3550?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2023-3550?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST