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CVE-2019-12521

CVSS v3.1 5.9 (Medium)
59% Progress
CVSS v2.0 4.3 (Medium)
43% Progress
EPSS 4.62 % (93th)
4.62% Progress
Affected Products 4
Advisories 13
Info CVSS EPSS Affected Configurations References Security Advisories Packages & Software OVAL Tools, Exploits & PoC Graph Web & Social Timeline

An issue was discovered in Squid through 4.7. When Squid is parsing ESI, it keeps the ESI elements in ESIContext. ESIContext contains a buffer for holding a stack of ESIElements. When a new ESIElement is parsed, it is added via addStackElement. addStackElement has a check for the number of elements in this buffer, but it's off by 1, leading to a Heap Overflow of 1 element. The overflow is within the same structure so it can't affect adjacent memory blocks, and thus just leads to a crash while processing.

Weaknesses
CWE-193
Off-by-one Error
CWE-787
Out-of-bounds Write
CVE Status
PUBLISHED
CNA
MITRE
Published Date
2020-04-15 19:15:12
(4 years ago)
Updated Date
2021-07-21 11:39:23
(3 years ago)

Affected Products

Canonical

Debian

Opensuse

Squid-cache

Configuration #1

    CPE23 From Up To
  Squid-cache Squid from 3.0 version and 3.5.28 and prior versions cpe:2.3:a:squid-cache:squid >= 3.0 <= 3.5.28
  Squid-cache Squid from 4.0 version and 4.7 and prior versions cpe:2.3:a:squid-cache:squid >= 4.0 <= 4.7
  Squid-cache Squid from 5.0 version and 5.0.1 and prior versions cpe:2.3:a:squid-cache:squid >= 5.0 <= 5.0.1

Configuration #2

    CPE23 From Up To
  Canonical Ubuntu Linux 16.04 cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts
  Canonical Ubuntu Linux 18.04 cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts
  Canonical Ubuntu Linux 19.10 cpe:2.3:o:canonical:ubuntu_linux:19.10
  Canonical Ubuntu Linux 20.04 cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts

Configuration #3

    CPE23 From Up To
  Debian Linux 9.0 cpe:2.3:o:debian:debian_linux:9.0
  Debian Linux 10.0 cpe:2.3:o:debian:debian_linux:10.0

Configuration #4

    CPE23 From Up To
  Opensuse Leap 15.1 cpe:2.3:o:opensuse:leap:15.1