Squid Web Proxy up to 4.14/5.0.5 Range Request denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Squid Web Proxy up to 4.14/5.0.5. Affected by this issue is some unknown functionality of the component Range Request Handler. The manipulation results in denial of service. This vulnerability was named CVE-2021-31808. The attack may be performed from remote. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Squid Web Proxy up to 4.14/5.0.5 (Firewall Software). Affected is some unknown functionality of the component Range Request Handler. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability.

The weakness was presented 05/28/2021. The advisory is shared for download at github.com. This vulnerability is traded as CVE-2021-31808. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1499.

The vulnerability scanner Nessus provides a plugin with the ID 252911 (Linux Distros Unpatched Vulnerability : CVE-2021-31808), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.15 or 5.0.6 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at squid-cache.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (252911). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 252911
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2021-31808

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Web Proxy 4.15/5.0.6
Patch: squid-cache.org

Timelineinfo

04/26/2021 🔍
05/28/2021 +32 days 🔍
05/28/2021 +0 days 🔍
08/20/2025 +1545 days 🔍

Sourcesinfo

Vendor: squid-cache.org

Advisory: github.com
Status: Confirmed

CVE: CVE-2021-31808 (🔍)
GCVE (CVE): GCVE-0-2021-31808
GCVE (VulDB): GCVE-100-175968

Entryinfo

Created: 05/28/2021 06:25
Updated: 08/20/2025 22:45
Changes: 05/28/2021 06:25 (40), 05/30/2021 11:44 (5), 08/20/2025 22:45 (16)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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