ruby-sanitize vulnerability

A security issue affects these releases of Ubuntu and its
derivatives:

* Ubuntu 20.04 LTS

Summary

Sanitize could be made to perform XSS attacks if it received
specially crafted input.

Software Description

* ruby-sanitize - allowlist-based HTML and CSS sanitizer

Details

Micha** Bentkowski discovered that Sanitize did not properly
sanitize some math or svg HTML under certain circumstances. A
remote attacker could potentially exploit this to conduct
cross-site scripting (XSS) attacks. (CVE-2020-4054)

Update instructions

The problem can be corrected by updating your system to the
following package versions:

Ubuntu 20.04 LTS
ruby-sanitize - 4.6.6-2.1~0.20.04.1

To update your system, please follow these instructions:
https://wiki.ubuntu.com/Security/Upgrades.

In general, a standard system update will make all the necessary
changes.

References

* CVE-2020-4054

--- Mystic BBS v1.12 A46 (Linux/64)
* Origin: BZ&BZ BBS (21:4/110)