An issue was discovered in Squid through 4.7.
Priority LOW 21CWE-269Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- High
- Impact type
- Privilege escalation
- Confidentiality · integrity · availability
- Low · Low · Low
- Fix status
- Deferred Red Hat: fix deferred
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-269.
Summary
An issue was discovered in Squid through 4.7. When Squid is run as root, it spawns its child processes as a lesser user, by default the user nobody. This is done via the leave_suid call. leave_suid leaves the Saved UID as 0. This makes it trivial for an attacker who has compromised the child process to escalate their privileges back to root.
Why it matters now
EPSS 0.00344 28th percentileScored 2026-11-07
Fix Deferred Red Hat: fix deferred
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:* | up to 4.7 | Vulnerable | squid-cache |
- cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:* Versions up to 4.7 Vulnerable ·squid-cache
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 5 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
Timeline
- 2026-10-02 Threatist record created from CVE-2019-12522
- 2026-10-03 Alias added: GHSA-rwjf-j42w-jfr4
References
More squid-cache Squid vulnerabilities
- TI-2025-38486 Squid vulnerable to information disclosure via authentication credential leakage in error handling CVSS 3.1CRITICAL 10.0
- TI-2024-16845 Denial of Service in HTTP Header parser in squid proxy CVSS 3.1HIGH 7.5
- TI-2024-16566 SQUID-2024:1 Denial of Service in HTTP Chunked Decoding CVSS 3.1HIGH 8.6
- TI-2023-26921 Denial of Service in HTTP Message Processing in Squid CVSS 3.1HIGH 8.6
- TI-2023-27496 SQUID-2023:10 Denial of Service in HTTP Request parsing CVSS 3.1HIGH 8.6
- TI-2023-25306 Squid: denial of service in http digest authentication CVSS 3.1HIGH 8.6
Sources
- CVE-2019-12522 · CVE Program
- CVE-2019-12522 · NVD
- FIRST EPSS
- GHSA-rwjf-j42w-jfr4 · GitHub Advisory Database · CC BY 4.0
- CVE-2019-12522 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences