diff-so-fancy up to 1.4.10 escape output

Summaryinfo

A vulnerability categorized as critical has been discovered in diff-so-fancy up to 1.4.10. This impacts an unknown function. Such manipulation leads to escape output. This vulnerability is referenced as CVE-2026-50642. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability, which was classified as critical, has been found in diff-so-fancy up to 1.4.10. Affected by this issue is an unknown functionality. The manipulation with an unknown input leads to a escape output vulnerability. Using CWE to declare the problem leads to CWE-116. The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved. Impacted is confidentiality, integrity, and availability. CVE summarizes:

diff‑so‑fancy does not properly sanitize non‑SGR terminal control sequences before outputting diff data. The application only strips ANSI SGR sequences while allowing other control characters, including carriage return (\r) and escape sequences (e.g., OSC, CSI), to pass through unsanitized. An attacker can embed malicious control sequences in filenames, diff metadata, or file content that are rendered directly in the terminal during diff viewing. This can lead to output manipulation, including filename spoofing, terminal screen clearing, and clipboard injection via supported escape sequences. Successful exploitation may mislead users during code review, alter terminal state, or result in unintended command execution through clipboard hijacking. This issue has been fixed in the commit 9c81294

The advisory is shared for download at cert.pl. This vulnerability is handled as CVE-2026-50642 since 06/05/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available.

Applying the patch 9c81294 is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-50278). Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

• diff-so-fancy

Version

• 1.4.0
• 1.4.1
• 1.4.2
• 1.4.3
• 1.4.4
• 1.4.5
• 1.4.6
• 1.4.7
• 1.4.8
• 1.4.9
• 1.4.10

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

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• 🔒
• 🔒

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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