vulnerability
MediaWiki: CVE-2020-35480: Observable Discrepancy
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 5 | (AV:N/AC:L/Au:N/C:P/I:N/A:N) | Dec 18, 2020 | Dec 29, 2020 | May 6, 2026 |
Severity
5
CVSS
(AV:N/AC:L/Au:N/C:P/I:N/A:N)
Published
Dec 18, 2020
Added
Dec 29, 2020
Modified
May 6, 2026
Description
An issue was discovered in MediaWiki before 1.35.1. Missing users (accounts that don't exist) and hidden users (accounts that have been explicitly hidden due to being abusive, or similar) that the viewer cannot see are handled differently, exposing sensitive information about the hidden status to unprivileged viewers. This exists on various code paths.
Solution
mediawiki-upgrade-latest
References
- CVE-2020-35480
- https://attackerkb.com/topics/CVE-2020-35480
- https://lists.debian.org/debian-lts-announce/2020/12/msg00034.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/STT5Z4A3BCXVH3WIPICWU2FP4IPIMUPC/
- https://lists.wikimedia.org/pipermail/mediawiki-announce/2020-December/000268.html
- https://phabricator.wikimedia.org/T120883
- https://www.debian.org/security/2020/dsa-4816
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2020-23151
- CWE-203
- EUVD-EUVD-2020-23151
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