The strListGetItem function in src/HttpHeaderTools.c in Squid 2.7 allows remote attackers…
Priority MEDIUM 48CWE-20Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- — Not recorded in CVSS 2.0
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · Partial
- Fix status
- Fixed
Attack profile from CVSS 2.0 · NVD. Fix status from CNA and Red Hat.
Summary
The strListGetItem function in src/HttpHeaderTools.c in Squid 2.7 allows remote attackers to cause a denial of service via a crafted auth header with certain comma delimiters that trigger an infinite loop of calls to the strcspn function.
Why it matters now
EPSS 0.34031 98th percentileScored 2026-11-07
Fix Fixed Red Hat: 1 advisory
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 · 3
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:squid-cache:squid:2.7:*:*:*:*:*:*:* | 2.7 | Vulnerable | squid-cache |
| cpe:2.3:a:squid-cache:squid:2.7:stable3:*:*:*:*:*:* | 2.7 stable3 | Vulnerable | squid-cache |
| cpe:2.3:a:squid-cache:squid:2.7:stable4:*:*:*:*:*:* | 2.7 stable4 | Vulnerable | squid-cache |
- cpe:2.3:a:squid-cache:squid:2.7:*:*:*:*:*:*:* Versions 2.7 Vulnerable ·squid-cache
- cpe:2.3:a:squid-cache:squid:2.7:stable3:*:*:*:*:*:* Versions 2.7 stable3 Vulnerable ·squid-cache
- cpe:2.3:a:squid-cache:squid:2.7:stable4:*:*:*:*:*:* Versions 2.7 stable4 Vulnerable ·squid-cache
Remediation
Red Hat 1 advisory
- RHSA-2010:0221 Released 2010-03-29 · Red Hat rating Lowsquid security and bug fix update
- Red Hat Enterprise Linux (v. 5 server) squid-7:2.6.STABLE21-6.el5, squid-7:2.6.STABLE21-6.el5.i386, squid-7:2.6.STABLE21-6.el5.ia64 +1
- Red Hat Enterprise Linux Desktop Workstation (v. 5 client) squid-7:2.6.STABLE21-6.el5, squid-7:2.6.STABLE21-6.el5.i386
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux (v. 5 server) | Fixed | RHSA-2010:0221 |
| Red Hat Enterprise Linux Desktop Workstation (v. 5 client) | Fixed | RHSA-2010:0221 |
Timeline
- 2026-10-02 Threatist record created from CVE-2009-2855
- 2026-10-03 Alias added: GHSA-7hrp-6jq3-pm4q
References
Other 8
- [oss-security] 20090803 Re: squid DoS in external auth header parser
- http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=534982
- [oss-security] 20090804 Re: squid DoS in external auth header parser
- http://www.squid-cache.org/bugs/show_bug.cgi?id=2541
- oval:org.mitre.oval:def:10592
- https://bugzilla.redhat.com/show_bug.cgi?id=518182
- [oss-security] 20090720 squid DoS in external auth header parser
- http://bugs.debian.org/cgi-bin/bugreport.cgi?msg=31%3Bfilename=diff%3Batt=1%3Bbug=534982
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-2009-2855 · CVE Program
- CVE-2009-2855 · NVD
- FIRST EPSS
- GHSA-7hrp-6jq3-pm4q · GitHub Advisory Database · CC BY 4.0
- CVE-2009-2855 · 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