Tinyproxy up to 1.11.2 src/reqs.c strip_return_port integer overflow

Summaryinfo

A vulnerability labeled as critical has been found in Tinyproxy up to 1.11.2. This affects the function strip_return_port of the file src/reqs.c. Executing a manipulation can lead to integer overflow. This vulnerability is handled as CVE-2025-63938. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability has been found in Tinyproxy up to 1.11.2 and classified as critical. This vulnerability affects the function strip_return_port of the file src/reqs.c. The manipulation with an unknown input leads to a integer overflow vulnerability. The CWE definition for the vulnerability is CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Tinyproxy through 1.11.2 contains an integer overflow vulnerability in the strip_return_port() function within src/reqs.c.

The advisory is shared for download at github.com. This vulnerability was named CVE-2025-63938 since 10/27/2025. The exploitation appears to be easy. The attack can be initiated remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 12/02/2025).

The vulnerability scanner Nessus provides a plugin with the ID 276975 (Linux Distros Unpatched Vulnerability : CVE-2025-63938), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (276975). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

• Firewall Software

Name

• Tinyproxy

Version

• 1.11.0
• 1.11.1
• 1.11.2

Website

• Product: https://github.com/tinyproxy/tinyproxy/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

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

Discussion