CVE-2021-29953
Publication date 24 June 2021
Last updated 1 August 2025
Ubuntu priority
Description
A malicious webpage could have forced a Firefox for Android user into executing attacker-controlled JavaScript in the context of another domain, resulting in a Universal Cross-Site Scripting vulnerability. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected. Further details are being temporarily withheld to allow users an opportunity to update.*. This vulnerability affects Firefox < 88.0.1 and Firefox for Android < 88.1.3.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| firefox | ||
| 20.04 LTS focal | Not in release | |
| 18.04 LTS bionic |
Not affected
|
|
| 16.04 LTS xenial |
Not affected
|
|
| 14.04 LTS trusty | Not in release | |
| thunderbird | ||
| 20.04 LTS focal | Not in release | |
| 18.04 LTS bionic |
Not affected
|
|
| 16.04 LTS xenial |
Not affected
|
|
| 14.04 LTS trusty | Not in release |
Notes
tyhicks
mozjs contains a copy of the SpiderMonkey JavaScript engine
alexmurray
As per the upstream advisory, this issue only affected Firefox for Android and so firefox on ubuntu is unaffected.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
6.1 · Medium
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | Required |
| Scope | Changed |
| Confidentiality | Low |
| Integrity impact | Low |
| Availability impact | None |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |