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Stack-based buffer overflow in Flat Assembler 1.71.21
CVE-2017-20228 is a stack-based buffer overflow in Flat Assembler version 1.71.21. According to the provided content, the flaw can be triggered by supplying oversized assembly input to the application. Malicious input exceeding 5895 bytes can overwrite the instruction pointer, indicating an out-of-bounds write condition on the stack. Successful exploitation enables construction of a return-oriented programming (ROP) chain, which can then be used to execute shell commands and achieve arbitrary code execution in the context of the vulnerable process.
What it means and what to do now: patch path, interim mitigations, and the assume-compromise checklist.
What an attacker gets, and what they’ve been doing with it.
Successful exploitation allows local arbitrary code execution. By overwriting the instruction pointer with oversized assembly input, an attacker can redirect control flow and execute a ROP chain, leading to shell command execution. The provided content indicates high impact to confidentiality, integrity, and availability.
If you can’t patch tonight, do this now.
Do not process untrusted or attacker-supplied assembly source files with Flat Assembler 1.71.21. Restrict local access to systems where the assembler is installed, limit execution to trusted users, and isolate the tool in a constrained environment such as a sandbox, container, or dedicated build host to reduce the impact of exploitation. Monitoring for crashes triggered by unusually large input files may also help detect attempted exploitation.
Patch, then assume compromise.
Upgrade from Flat Assembler 1.71.21 to a fixed version if one is available from the vendor. If no patched release is currently available in the provided information, replace or discontinue use of the vulnerable version and validate all assembly input handling paths. Review vendor advisories and referenced security guidance for an official fix.
No public exploits tracked yet. Mallory keeps watching.
Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.
4 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.