GNU cflow up to 1.8 Lexer c.c yylex buffer overflow

Summaryinfo

A vulnerability was found in GNU cflow up to 1.8 and classified as critical. Affected by this issue is the function yylex of the file c.c of the component Lexer. Such manipulation leads to buffer overflow. This vulnerability is uniquely identified as CVE-2025-8736. Local access is required to approach this attack. Moreover, an exploit is present.

Detailsinfo

A vulnerability, which was classified as critical, has been found in GNU cflow up to 1.8. Affected by this issue is the function yylex of the file c.c of the component Lexer. The manipulation with an unknown input leads to a buffer overflow vulnerability. Using CWE to declare the problem leads to CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. Impacted is confidentiality, integrity, and availability.

The advisory is shared for download at lists.gnu.org. This vulnerability is handled as CVE-2025-8736. The exploitation is known to be easy. The attack needs to be approached locally. Technical details as well as a public exploit are known.

The exploit is available at drive.google.com. It is declared as proof-of-concept. The vulnerability scanner Nessus provides a plugin with the ID 253549 (Linux Distros Unpatched Vulnerability : CVE-2025-8736), 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 databases at Tenable (253549) and EUVD (EUVD-2025-24013). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Vendor

• GNU

Name

• cflow

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8

License

• open-source

Website

• Vendor: https://www.gnu.org/

CPE 2.3info

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CPE 2.2info

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Submitinfo

Accepted

• Submit #622329: GNU cflow cflow cflow (GNU cflow) the newest master (0a19319e282506ff88d19e630380cd5069e893ed ) in cflow.git - GNU cflow Buffer Overflow (by lists.gnu.org)

Duplicate

• Submit #XXXXXX: Xxx Xxxxx Xxxxx Xxxxx (xxx Xxxxx) Xxx Xxxxxx Xxxxxx (xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx ) Xx Xxxxx.xxx - Xxx Xxxxx Xxxxx Xxxxxx Xxxxxxxxx (by nipc-cxd)

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

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