CVE-2026-48813 in flawfinder
Summary
by MITRE • 08/11/2026
Flawfinder is a a static analysis tool for finding vulnerabilities in C/C++ source code. Versions prior to 2.0.20 have an improper input neutralization issue leading to output manipulation, specifically, Terminal/ANSI Escape Sequence Injection and XML Injection. A malicious file whose name contains ANSI escape sequences can end up being included in flawfinder's standard terminal output, with many effects. Untrusted fields (such as filenames, categories, or code context text) were not properly sanitized when generating structured reports. An attacker could exploit this to corrupt CSV formats or inject arbitrary XML attributes into SonarQube outputs via output_sonar(). It impacts those who use flawfinder to evaluate intentionally malicious filenames or file contents. This issue has been fully patched in Version 2.0.20 (released 2026-05-16). There is no configuration-based workaround within older versions of flawfinder. If an immediate upgrade is not possible, users can mitigate the risk by pre-scanning filenames, inspecting raw output, and/or restricting untrusted inputs.
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Analysis
by VulDB Data Team • 08/11/2026
Flawfinder serves as a critical static analysis tool designed to identify potential security vulnerabilities within C/C++ source code through automated examination of program structures and coding patterns. The vulnerability discovered in versions prior to 2.0.20 represents a significant weakness in input sanitization that directly impacts the tool's output integrity and security posture. This flaw manifests as an improper input neutralization issue that specifically targets the tool's handling of terminal output generation and structured reporting mechanisms. The vulnerability stems from insufficient validation and sanitization of untrusted data elements including filenames, code context text, and category information that are processed during analysis operations.
The technical implementation of this vulnerability enables attackers to manipulate the tool's output through carefully crafted malicious filenames containing ANSI escape sequences that are not properly neutralized before being rendered in terminal environments. This creates opportunities for terminal escape sequence injection that can alter display behavior, potentially masking or obfuscating important security warnings and alerts. Additionally, the flaw extends to XML injection capabilities within the SonarQube integration functionality through the output_sonar() method, where unescaped input data can corrupt structured reports and introduce arbitrary XML attributes into generated outputs. The root cause lies in the tool's failure to implement proper input sanitization routines for fields that are directly incorporated into formatted output strings without adequate encoding or escaping mechanisms.
The operational impact of this vulnerability extends beyond simple output corruption, creating potential security risks for organizations relying on flawfinder for code quality assessment and vulnerability detection. When processing intentionally malicious filenames or content, attackers can exploit the injection vectors to manipulate analysis results, potentially causing security alerts to be hidden or distorted within terminal displays. The XML injection capability poses particular risk when integrated with SonarQube platforms, as it could allow attackers to inject malicious attributes or elements into structured reports that are consumed by security monitoring systems. This vulnerability affects users who may inadvertently process untrusted code inputs through flawfinder, creating a vector for indirect exploitation of downstream security tools and systems that rely on accurate analysis output.
Security practitioners should recognize this vulnerability as aligning with CWE-116 improper input neutralization and CWE-74 XML injection weaknesses, both of which are commonly exploited in static analysis tool attacks. The ATT&CK framework categorizes this issue under TA0005 Defense Evasion techniques, specifically targeting T1070 Command and Scripting Interpreter for output manipulation and T1566 Social Engineering for potential user deception through manipulated terminal displays. Organizations using older flawfinder versions without immediate upgrade capability must implement compensating controls including pre-scanning of all filenames for suspicious sequences, manual inspection of raw tool output before processing, and strict input validation policies that prevent untrusted content from entering the analysis pipeline. The patch released in version 2.0.20 addresses these issues through comprehensive input sanitization routines that properly encode or escape all potentially dangerous characters in output generation contexts, ensuring that terminal escape sequences and XML special characters are appropriately handled during report formatting operations.