CVE-2021-33620
Publication date 28 May 2021
Last updated 18 August 2025
Ubuntu priority
Description
Squid before 4.15 and 5.x before 5.0.6 allows remote servers to cause a denial of service (affecting availability to all clients) via an HTTP response. The issue trigger is a header that can be expected to exist in HTTP traffic without any malicious intent by the server.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| squid3 | 26.10 stonking | Not in release |
| 26.04 LTS resolute | Not in release | |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| 20.04 LTS focal | Not in release | |
| 18.04 LTS bionic |
Fixed in 3.5.27-1ubuntu1.11
|
|
| 16.04 LTS xenial |
Vulnerable
|
|
| 14.04 LTS trusty | Not in release | |
| squid | 26.10 stonking |
Fixed in 4.13-10ubuntu1
|
| 26.04 LTS resolute |
Fixed in 4.13-10ubuntu1
|
|
| 24.04 LTS noble |
Fixed in 4.13-10ubuntu1
|
|
| 22.04 LTS jammy |
Fixed in 4.13-10ubuntu1
|
|
| 20.04 LTS focal |
Fixed in 4.10-1ubuntu1.4
|
|
| 18.04 LTS bionic | Not in release | |
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release |
Patch details
| Package | Patch details |
|---|---|
| squid |
Severity score breakdown
CVSS version: CVSS v3.0
Base score
6.5 · Medium
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
References
Related Ubuntu Security Notices (USN)
- USN-4981-1
- Squid vulnerabilities
- 3 June 2021