CVE-2020-35479

Public Exploit

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.

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.05% Top 25%
Vendor Advisory debian.org Vendor Advisory fedoraproject.org Vendor Advisory wikimedia.org Vendor Advisory wikimedia.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://phabricator.wikimedia.org/T268938 vendor advisory exploit
https://lists.wikimedia.org/pipermail/mediawiki-announce/2020-December/000268.html vendor advisory mailing list release notes
https://www.debian.org/security/2020/dsa-4816 third party advisory vendor advisory
https://lists.debian.org/debian-lts-announce/2020/12/msg00034.html third party advisory mailing list
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/STT5Z4A3BCXVH3WIPICWU2FP4IPIMUPC/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-35479?
CVE-2020-35479 has been scored as a medium severity vulnerability.
How to fix CVE-2020-35479?
To fix CVE-2020-35479, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-35479 being actively exploited in the wild?
It is possible that CVE-2020-35479 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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