Tinyproxy up to 1.11.3 src/acl.c acl_string_processing access control

CVSS Meta Temp Score
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CTI Interest Score
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5.9$0-$5k0.00+

Summaryinfo

A vulnerability identified as critical has been detected in Tinyproxy up to 1.11.3. This affects the function acl_string_processing of the file src/acl.c. The manipulation leads to access control. This vulnerability is listed as CVE-2026-125371. The attack may be initiated remotely. There is no available exploit. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability was found in Tinyproxy up to 1.11.3 and classified as critical. This issue affects the function acl_string_processing of the file src/acl.c. The manipulation with an unknown input leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Tinyproxy through 1.11.3 contains an access control bypass vulnerability in acl_string_processing() in src/acl.c that compares only trailing hostname characters without checking DNS label boundaries. Attackers controlling the PTR record for their source IP, such as untrusted.net, can satisfy an 'Allow trusted.net' entry to use the proxy despite deny-by-default ACLs.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-125371 since 11/09/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

Applying the patch 3991ac8f98c6a9f05b3265018b812dbf2ca92c28 is able to eliminate this problem.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.1
VulDB Meta Temp Score: 5.9

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.8
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Access control
CWE: CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: 3991ac8f98c6a9f05b3265018b812dbf2ca92c28

Timelineinfo

11/09/2026 CVE reserved
11/09/2026 +0 days VulDB entry created
11/10/2026 +0 days Advisory disclosed
11/10/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CNA: VulnCheck
CVE: CVE-2026-125371 (🔒)

GCVE (CVE): GCVE-0-2026-125371
GCVE (VulDB): GCVE-100-433463

Entryinfo

Created: 11/10/2026 00:59
Changes: 11/10/2026 00:59 (77)
Complete: 🔍
Cache ID: 216::103

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