Medium severity · published Dec 18, 2020
CVE-2020-35479
MediaWiki before 1.35.1 allows XSS via BlockLogFormatter.php
6.1
CVSS
1.5%
EPSS
No
On KEV
Description
MediaWiki before 1.35.1 allows XSS via BlockLogFormatter.php. Language::translateBlockExpiry itself does not escape in all code paths. For example, the return of Language::userTimeAndDate is is always unsafe for HTML in a month value. This affects MediaWiki 1.12.0 and later.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)1.5% · higher than 74% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
FE
Fedora · Fedoraproject
33 · source: NVD
ME
Mediawiki · Mediawiki
1.12.0 before 1.35.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-35479
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-35479
Mailing List
https://lists.debian.org/debian-lts-announce/2020/12/msg00034.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/STT5Z4A3BCXVH3WIPICWU2FP4IPIMUPC/
Mailing List
https://lists.wikimedia.org/pipermail/mediawiki-announce/2020-December/000268.html
Exploit
https://phabricator.wikimedia.org/T268938
Third Party Advisory
https://www.debian.org/security/2020/dsa-4816
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