QID 198400

Date Published: 2021-06-10

QID 198400: Ubuntu Security Notification for Squid vulnerabilities (USN-4981-1)

Squid incorrectly handled requests with the urn: scheme.
Squid incorrectly handled requests to the cache manager api.
Squid incorrectly handled certain response headers.
Squid incorrectly handled range request processing.
Squid incorrectly handled certain http responses.

Note: The preceding description block is extracted directly from the security advisory. Using automation, we have attempted to clean and format it as much as possible without introducing additional issues.

a remote attacker could possibly use this issue to cause squid to consume resources, leading to a denial of service.
(cve-2021-28651).
A remote attacker with access privileges could possibly use this issue to cause squid to consume resources, leading to a denial of service.
This issue was only addressed in ubuntu 20.04 lts, ubuntu 20.10, and ubuntu 21.04. (
cve-2021-28652).
A remote attacker could possibly use this issue to cause squid to crash, resulting in a denial of service.
This issue was only affected ubuntu 20.04 lts, ubuntu 20.10, and ubuntu 21.04. (
cve-2021-28662).
A remote attacker could possibly use this issue to cause squid to crash, resulting in a denial of service. (
cve-2021-31806, cve-2021-31807, cve-2021-31808).
A remote attacker could possibly use this issue to cause squid to crash, resulting in a denial of service. (
cve-2021-33620).

  • CVSS V3 rated as High - 6.5 severity.
  • CVSS V2 rated as Medium - 5.4 severity.
  • Solution
    Refer to Ubuntu advisory: USN-4981-1 for affected packages and patching details, or update with your package manager.
    Vendor References
    Software Advisories
    Advisory ID Software Component Link
    USN-4981-1 Ubuntu Linux URL Logo usn.ubuntu.com/4981-1
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