Squid Web Proxy up to 5.6/6.3 SSL Certificate Validation out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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7.1$0-$5k0.00

Summaryinfo

A vulnerability was found in Squid Web Proxy up to 5.6/6.3. It has been rated as problematic. Affected is an unknown function of the component SSL Certificate Validation. The manipulation leads to out-of-bounds. This vulnerability is referenced as CVE-2023-46724. Remote exploitation of the attack is possible. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Squid Web Proxy up to 5.6/6.3 (Firewall Software) and classified as problematic. This issue affects an unknown function of the component SSL Certificate Validation. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is availability. The summary by CVE is:

Squid is a caching proxy for the Web. Due to an Improper Validation of Specified Index bug, Squid versions 3.3.0.1 through 5.9 and 6.0 prior to 6.4 compiled using `--with-openssl` are vulnerable to a Denial of Service attack against SSL Certificate validation. This problem allows a remote server to perform Denial of Service against Squid Proxy by initiating a TLS Handshake with a specially crafted SSL Certificate in a server certificate chain. This attack is limited to HTTPS and SSL-Bump. This bug is fixed in Squid version 6.4. In addition, patches addressing this problem for the stable releases can be found in Squid's patch archives. Those who you use a prepackaged version of Squid should refer to the package vendor for availability information on updated packages.

The weakness was published 11/01/2023. The advisory is shared at github.com. The identification of this vulnerability is CVE-2023-46724 since 10/25/2023. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 236724 (Alibaba Cloud Linux 3 : 0020: squid:4 (ALINUX3-SA-2024:0020)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.9 or 6.4 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (236724). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 7.1

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

NVD Base Score: 7.5
NVD Vector: 🔍

CNA Base Score: 8.6
CNA Vector (GitHub, Inc.): 🔍

CVSSv2info

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

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
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: 236724
Nessus Name: Alibaba Cloud Linux 3 : 0020: squid:4 (ALINUX3-SA-2024:0020)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Web Proxy 5.9/6.4
Patch: github.com

Timelineinfo

10/25/2023 🔍
11/01/2023 +7 days 🔍
11/01/2023 +0 days 🔍
05/16/2025 +562 days 🔍

Sourcesinfo

Vendor: squid-cache.org

Advisory: b70f864940225dfe69f9f653f948e787f99c3810
Status: Confirmed

CVE: CVE-2023-46724 (🔍)
GCVE (CVE): GCVE-0-2023-46724
GCVE (VulDB): GCVE-100-244265

Entryinfo

Created: 11/01/2023 20:28
Updated: 05/16/2025 18:03
Changes: 11/01/2023 20:28 (50), 11/29/2023 17:52 (2), 11/29/2023 17:59 (12), 02/14/2025 07:12 (16), 05/16/2025 18:03 (2)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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