VDB
ALPINE-CVE-2019-12521
ALPINE-CVE-2019-12521
PUBLISHED
CVSS 5.900000095367432 MEDIUM
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.
Risk Scores
CVSS v3.1
5.900000095367432
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Alpine:v3.11 | squid | 3.3.11-r0, 4.9-r0, 4.8-r1 |
| Alpine:v3.10 | squid | 4.8-r1, 3.2.0.17-r0, 3.2.0.17-r1 |
| Alpine:v3.9 | squid | 4.8-r1, 4.8-r0, 4.4-r1 |
Timeline
- Apr 15, 2020 CVE Published
- Nov 19, 2025 CVE Updated
- Apr 30, 2026 Distribution Patch