Squid Web Proxy up to 4.14/5.0.5 urn Scheme memory allocation

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability was found in Squid Web Proxy up to 4.14/5.0.5. It has been declared as problematic. This affects an unknown function of the component urn Scheme Handler. The manipulation results in memory allocation. This vulnerability is identified as CVE-2021-28651. The attack can be executed remotely. There is not any exploit available. It is recommended to 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 processing of the component urn Scheme Handler. The manipulation with an unknown input leads to a memory allocation vulnerability. CWE is classifying the issue as CWE-789. The product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated. This is going to have an impact on availability.

The weakness was released 05/28/2021. The advisory is available at github.com. This vulnerability is traded as CVE-2021-28651. The technical details are unknown and an exploit is not available.

The vulnerability scanner Nessus provides a plugin with the ID 254409 (RHEL 7 : squid (RHSA-2025:14414)), 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.

The vulnerability is also documented in the vulnerability database at Tenable (254409). If you want to get best quality of vulnerability data, you may have to visit VulDB.

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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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory allocation
CWE: CWE-789 / CWE-400 / 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: 254409
Nessus Name: RHEL 7 : squid (RHSA-2025:14414)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Web Proxy 4.15/5.0.6

Timelineinfo

03/17/2021 🔍
05/28/2021 +71 days 🔍
05/28/2021 +0 days 🔍
08/25/2025 +1550 days 🔍

Sourcesinfo

Vendor: squid-cache.org

Advisory: github.com
Status: Confirmed

CVE: CVE-2021-28651 (🔍)
GCVE (CVE): GCVE-0-2021-28651
GCVE (VulDB): GCVE-100-175986

Entryinfo

Created: 05/28/2021 06:52
Updated: 08/25/2025 19:17
Changes: 05/28/2021 06:52 (39), 05/30/2021 14:00 (5), 08/25/2025 19:17 (16)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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