Lucene search

K
cve[email protected]CVE-2019-12521
HistoryApr 15, 2020 - 7:15 p.m.

CVE-2019-12521

2020-04-1519:15:00
CWE-787
CWE-193
web.nvd.nist.gov
292
squid
cve-2019-12521
esi
security
vulnerability
parsing
heap overflow

5.9 Medium

CVSS3

Attack Vector

NETWORK

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

7.5 High

AI Score

Confidence

High

4.3 Medium

CVSS2

Access Vector

NETWORK

Access Complexity

MEDIUM

Authentication

NONE

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

PARTIAL

AV:N/AC:M/Au:N/C:N/I:N/A:P

0.034 Low

EPSS

Percentile

91.4%

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.

5.9 Medium

CVSS3

Attack Vector

NETWORK

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

7.5 High

AI Score

Confidence

High

4.3 Medium

CVSS2

Access Vector

NETWORK

Access Complexity

MEDIUM

Authentication

NONE

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

PARTIAL

AV:N/AC:M/Au:N/C:N/I:N/A:P

0.034 Low

EPSS

Percentile

91.4%