// For flags

CVE-2009-2855

squid: DoS (100% CPU use) while processing certain external ACL helper HTTP headers

Severity Score

7.5
*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

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.

La función strListGetItem en src/HttpHeaderTools.c en Squid v2.7 a permite a los atacantes remotos causar una denegación de servicio a través de una cabecera auth manipulada con ciertos delimitadores coma que lanzan un bucle infinito de llamadas a la función strcspn.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial
Attack Vector
Adjacent
Attack Complexity
Medium
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2009-08-18 CVE Reserved
  • 2009-08-18 CVE Published
  • 2024-08-07 CVE Updated
  • 2025-03-30 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-20: Improper Input Validation
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Squid-cache
Search vendor "Squid-cache"
Squid
Search vendor "Squid-cache" for product "Squid"
2.7
Search vendor "Squid-cache" for product "Squid" and version "2.7"
-
Affected
Squid-cache
Search vendor "Squid-cache"
Squid
Search vendor "Squid-cache" for product "Squid"
2.7
Search vendor "Squid-cache" for product "Squid" and version "2.7"
stable3
Affected
Squid-cache
Search vendor "Squid-cache"
Squid
Search vendor "Squid-cache" for product "Squid"
2.7
Search vendor "Squid-cache" for product "Squid" and version "2.7"
stable4
Affected