PT-2026-33204 · Wikimedia Foundation+3 · Checkuser+1

Kostajh · Published 2026-04-03 · Updated 2026-05-14 · CVE-2026-34090

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

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

Name of the Vulnerable Software and Affected Versions Wikimedia Foundation CheckUser versions 1.45.0 through 1.45.1

Description An issue exists that allows the exposure of sensitive information to an unauthorized actor.

Recommendations Update to version 1.45.2.

Fix

Information Disclosure

Weakness Enumeration

CWE-200

Related Identifiers

CVE-2026-34090

Affected Products

Checkuser

Mediawiki

References · 12

• https://osv.dev/vulnerability/UBUNTU-CVE-2026-34090 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-34090 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2026-34090 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-34090 · Security Note
• https://phabricator.wikimedia.org/T411366 · Patch
• https://ubuntu.com/security/CVE-2026-34090 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-34090 · Vendor Advisory
• https://lists.wikimedia.org/hyperkitty/list/[e-mail]/thread/DIBLSBHISKX6NFRUFNOGZRVW42E7R2QP · Note
• https://t.me/cveNotify/163485 · Telegram Post
• https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/1240641 · Note
• https://twitter.com/CVEnew/status/2053932476108849472 · Twitter Post
• https://twitter.com/infoflowcloud/status/2053933428928643526 · Twitter Post