CVE-2020-35480
An issue was discovered in MediaWiki before 1.35.1. Missing users (accounts that don't exist) and...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
5.3
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.
- Record
CVE-2020-35480- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:P/I:N/A:N - Weakness
- CWE-203
- Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2020-35480- Updated
- 2026-11-02
EUVDEUVD-2020-23151 No score
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.
- Record
EUVD-2020-23151- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-6wfj-pw33-8cr3
5.3
An issue was discovered in MediaWiki before 1.35.1. Missing users (accounts that don't exist) and...
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.
- Record
GHSA-6wfj-pw33-8cr3- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Weakness
- CWE-200, CWE-203
- Updated
- 2026-11-02
OSV
5.3
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.
- Record
CVE-2020-35480- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVDEBIAN-CVE-2020-35480
5.3
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.
- Record
DEBIAN-CVE-2020-35480- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVUBUNTU-CVE-2020-35480
5.3
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.
- Record
UBUNTU-CVE-2020-35480- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVBIT-mediawiki-2020-35480 No score
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.
- Record
BIT-mediawiki-2020-35480- Updated
- 2026-11-02
OSVMGASA-2021-0086 No score
Updated mediawiki packages fix security vulnerability
In MediaWiki before 1.31.11, the messages userrights-expiry-current and userrights-expiry-none can contain raw HTML. XSS can happen when a user visits Special:UserRights but does not have rights to change all userrights, and the table on the left side has unchangeable groups in it. The right column with the changeable groups is not affected and is escaped correctly (CVE-2020-35475).
MediaWiki before 1.31.11 blocks legitimate attempts to hide log entries in some situations. If one sets MediaWiki:Mainpage to Special:MyLanguage/Main Page, visits a log entry on Special:Log, and toggles the "Change visibility of selected log entries" checkbox (or a tags checkbox) next to it, there is a redirection to the main page's action=historysubmit instead of the desired behavior in which a revision-deletion form appears (CVE-2020-35477).
MediaWiki before 1.31.11 allows XSS via BlockLogFormatter.php. Language::translateBlockExpiry itself does not escape in all code paths. For example, the return of Language::userTimeAndDate is always unsafe for HTML in a month value (CVE-2020-35479).
An issue was discovered in MediaWiki before 1.31.11. 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 (CVE-2020-35480).
- Record
MGASA-2021-0086- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
mediawikiBitnami |
before 1.35.1 | 1.35.1 |
mediawikiDebian:12 |
before 1:1.35.1-1 | 1:1.35.1-1 |
mediawikiDebian:13 |
before 1:1.35.1-1 | 1:1.35.1-1 |
mediawikiDebian:14 |
before 1:1.35.1-1 | 1:1.35.1-1 |
mediawikiDebian:9 From an advisory covering 4 CVEs |
before 1:1.27.7-1~deb9u7, plus listed versions 1:1.27.3-11:1.27.4-11:1.27.4-1~bpo8+11:1.27.4-1~deb9u11:1.27.4-2 Show 9 moreShow less1:1.27.4-31:1.27.5-1~deb9u11:1.27.6-1~deb9u11:1.27.7-1~deb9u11:1.27.7-1~deb9u21:1.27.7-1~deb9u31:1.27.7-1~deb9u41:1.27.7-1~deb9u51:1.27.7-1~deb9u6 |
1:1.27.7-1~deb9u7 |
mediawikiDebian:10 From an advisory covering 4 CVEs |
before 1:1.31.12-1~deb10u1, plus listed versions 1:1.31.10-1~deb10u11:1.31.2-11:1.31.4-11:1.31.4-1~deb10u11:1.31.5-1 Show 7 moreShow less1:1.31.5-21:1.31.5-31:1.31.6-11:1.31.6-1~deb10u11:1.31.7-11:1.31.7-1~deb10u11:1.31.8-1 |
1:1.31.12-1~deb10u1 |
mediawikiMageia:7 From an advisory covering 4 CVEs |
before 1.31.12-1.mga7 | 1.31.12-1.mga7 |
mediawikiUbuntu:18.04:LTS |
All versions, plus listed versions 1:1.27.3-11:1.27.4-11:1.27.4-21:1.27.4-3 |
None known |
mediawikiUbuntu:Pro:20.04:LTS |
All versions, plus listed versions 1:1.31.2-1ubuntu11:1.31.5-11:1.31.5-1ubuntu11:1.31.5-21:1.31.5-3 Show 4 moreShow less1:1.31.5-3ubuntu11:1.31.6-11:1.31.7-11:1.31.7-1ubuntu0.1~esm1 |
None known |
mediawikiUbuntu:Pro:22.04:LTS |
All versions, plus listed versions 1:1.35.3-11:1.35.4-11:1.35.5-11:1.35.5-1ubuntu11:1.35.5-1ubuntu21:1.35.5-1ubuntu31:1.35.6-11:1.35.6-1ubuntu0.1~esm1 |
None known |
Show 4 moreShow less
| Package | Affected | Fixed |
|---|---|---|
mediawikiUbuntu:Pro:24.04:LTS |
All versions, plus listed versions 1:1.39.4-21:1.39.5-11:1.39.6-11:1.39.7-11:1.39.7-1ubuntu0.1~esm1 |
None known |
mediawikiUbuntu:25.10 |
All versions, plus listed versions 1:1.43.1+dfsg-11:1.43.1+dfsg-21:1.43.3+dfsg-1 |
None known |
mediawikiUbuntu:26.10 |
All versions, plus listed versions 1:1.43.8+dfsg-21:1.43.9+dfsg-11:1.43.9+dfsg-1ubuntu1 |
None known |
mediawikiUbuntu:26.04:LTS |
All versions, plus listed versions 1:1.43.3+dfsg-11:1.43.5+dfsg-11:1.43.6+dfsg-21:1.43.8+dfsg-11:1.43.8+dfsg-2 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-35480 is a medium vulnerability (CVSS 5.3) in Mediawiki, published December 18, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.49%, the 74th percentile. Fixed in mediawiki 1.35.1.
References
phabricator.wikimedia.org/T120883
lists.wikimedia.org/pipermail/mediawiki-announce/2020-December/000268.html
debian.org/security/2020/dsa-4816
lists.debian.org/debian-lts-announce/2020/12/msg00034.html
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/STT5Z4A3BCXVH3WIPICWU2FP4IPIMUPC
nvd.nist.gov/vuln/detail/CVE-2020-35480
Show 9 moreShow less
lists.fedoraproject.org/archives/list/[email protected]/message/STT5Z4A3BCXVH3WIPICWU2FP4IPIMUPC
github.com/advisories/GHSA-6wfj-pw33-8cr3
security-tracker.debian.org/tracker/CVE-2020-35480
advisories.mageia.org/MGASA-2021-0086.html
bugs.mageia.org/show_bug.cgi?id=27781
lists.wikimedia.org/pipermail/mediawiki-announce/2020-December/000269.html
ubuntu.com/security/CVE-2020-35480
lists.wikimedia.org/pipermail/wikitech-l/2020-December/094126.html
cve.org/CVERecord?id=CVE-2020-35480