Squid
CVE-2021-31808
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Integer overflow checks
MITRE ATT&CK
1 technique across 1 tactic: Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 6.5 (MEDIUM). Attack characteristics: network attack vector, low complexity, low privileges required, no user interaction not required. Public proof-of-concept exploit code is available. |
| Exploit ScenarioDerived | A remote attacker could cause unexpected behavior through arithmetic overflow by sending crafted requests to the affected application. |
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Alert meAnalysisAI
An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Validate arithmetic operations, use safe integer libraries, check bounds before allocation.
Affects your stack
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Technical ContextAI · show details
This vulnerability is classified as Integer Overflow (CWE-190), which allows attackers to cause unexpected behavior through arithmetic overflow. An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to an input-validation bug, it is vulnerable to a Denial of Service attack (against all clients using the proxy). A client sends an HTTP Range request to trigger this. Affected products include: Squid-Cache Squid, Debian Debian Linux, Netapp Cloud Manager, Fedoraproject Fedora. Version information: before 4.15.
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Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to an input-validation bug, it is vulnerable to a Denial of Service attack (against all clients using the proxy). A client sends an HTTP Range request to trigger this.
Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Integer overflow occurs when an arithmetic operation produces a result that exceeds the maximum value a given integer type can store.
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)NVD
client_side.cc in Squid before 3.5.18 and 4.x before 4.0.10 does not properly ignore the Host header when absolute-URI i
Squid is vulnerable to a Denial of Service, where a remote attacker can perform buffer overflow attack by writing up to
Buffer overflow in Squid 3.x before 3.5.17 and 4.x before 4.0.9 allows remote attackers to execute arbitrary code via cr
client_side_request.cc in Squid 3.x before 3.5.18 and 4.x before 4.0.10 allows remote servers to cause a denial of servi
Heap-based buffer overflow in the Icmp6::Recv function in icmp/Icmp6.cc in the pinger utility in Squid before 3.5.16 and
client_side_request.cc in Squid 3.2.x before 3.2.13 and 3.3.x before 3.3.8 allows remote attackers to cause a denial of
Buffer overflow in the idnsALookup function in dns_internal.cc in Squid 3.2 through 3.2.11 and 3.3 through 3.3.6 allows
mime_header.cc in Squid before 3.5.18 allows remote attackers to bypass intended same-origin restrictions and possibly c
The pinger in Squid 3.x before 3.4.8 allows remote attackers to obtain sensitive information or cause a denial of servic
HttpHdrRange.cc in Squid 3.x before 3.3.12 and 3.4.x before 3.4.6 allows remote attackers to cause a denial of service (
Squid 3.x before 3.5.15 and 4.x before 4.0.7 does not properly append data to String objects, which allows remote server
Squid 3.x before 3.5.16 and 4.x before 4.0.8 improperly perform bounds checking, which allows remote attackers to cause
Exploit-DB