VULNERABILITY INTELLIGENCE
CVE-2019-12521
CVSS score5.9 MEDIUM
EPSS probability5.91%
CISA KEVNot currently listed
Published2020-04-15
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Description
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.
Weakness classification
- nvd@nist.gov: CWE-193
Primary references
- cve@mitre.org — Mailing List, Third Party Advisory
- cve@mitre.org — Mailing List, Patch, Third Party Advisory
- cve@mitre.org — Third Party Advisory
- cve@mitre.org — Mailing List, Third Party Advisory
- cve@mitre.org — Third Party Advisory
- cve@mitre.org — Third Party Advisory
- cve@mitre.org — Third Party Advisory
- cve@mitre.org — Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Mailing List, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Mailing List, Patch, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Mailing List, Third Party Advisory