CVE Vulnerabilities

CVE-2021-28652

Missing Release of Memory after Effective Lifetime

Published: May 27, 2021 | Modified: Nov 07, 2023
CVSS 3.x
4.9
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
CVSS 2.x
4 MEDIUM
AV:N/AC:L/Au:S/C:N/I:N/A:P
RedHat/V2
RedHat/V3
6.8 MODERATE
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
Ubuntu
LOW

An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to incorrect parser validation, it allows a Denial of Service attack against the Cache Manager API. This allows a trusted client to trigger memory leaks that. over time, lead to a Denial of Service via an unspecified short query string. This attack is limited to clients with Cache Manager API access privilege.

Weakness

The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory.

Affected Software

Name Vendor Start Version End Version
Squid Squid-cache 1.0 (including) 4.15 (excluding)
Squid Squid-cache 5.0 (including) 5.0.6 (excluding)
Red Hat Enterprise Linux 8 RedHat squid:4-8050020210618131503.b4937e53 *
Squid Ubuntu devel *
Squid Ubuntu focal *
Squid Ubuntu groovy *
Squid Ubuntu hirsute *
Squid Ubuntu impish *
Squid Ubuntu jammy *
Squid Ubuntu trusty *
Squid Ubuntu upstream *
Squid3 Ubuntu bionic *
Squid3 Ubuntu esm-infra/xenial *
Squid3 Ubuntu trusty *
Squid3 Ubuntu xenial *

Potential Mitigations

  • Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone.
  • For example, glibc in Linux provides protection against free of invalid pointers.
  • When using Xcode to target OS X or iOS, enable automatic reference counting (ARC) [REF-391].
  • To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std::auto_ptr (defined by ISO/IEC ISO/IEC 14882:2003), std::shared_ptr and std::unique_ptr (specified by an upcoming revision of the C++ standard, informally referred to as C++ 1x), or equivalent solutions such as Boost.

References