PT-2020-5765 · Squid+8 · Squid+9

Jeriko One

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Published

2019-07-15

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Updated

2022-08-19

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CVE-2019-12521

CVSS v3.1

5.9

Medium

VectorAV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Name of the Vulnerable Software and Affected Versions: Squid versions through 4.7
Description: An issue was discovered in Squid when parsing ESI. The ESIContext contains a buffer for holding a stack of ESIElements. When a new ESIElement is parsed, it is added via the addStackElement function. However, addStackElement has a check for the number of elements in this buffer that is off by 1, leading to a Heap Overflow of 1 element. The overflow is within the same structure, so it cannot affect adjacent memory blocks, and thus just leads to a crash while processing. This can be exploited by a remote attacker to cause a denial of service.
Recommendations: For Squid versions through 4.7, update to a version that fixes this issue to prevent a potential crash while processing ESI elements. At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Memory Corruption

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Weakness Enumeration

Related Identifiers

ALSA-2020:4743
ALT-PU-2019-2264
ALT-PU-2019-2271
ALT-PU-2020-3140
ALT-PU-2020-3142
BDU:2021-01724
CESA-2020_4743
CVE-2019-12521
DLA-2278-1
DSA-4682-1
OESA-2022-1851
OPENSUSE-SU-2020:0623-1
OPENSUSE-SU-2020_0623-1
RHSA-2020:4743
RHSA-2020_4743
RLSA-2020:4743
SUSE-SU-2020:1134-1
SUSE-SU-2020:1156-1
SUSE-SU-2020:1227-1
SUSE-SU-2020:14460-1
USN-4356-1

Affected Products

Alt Linux
Almalinux
Centos
Linuxmint
Red Hat
Rocky Linux
Squid
Squid Cache
Suse
Ubuntu