CVE-2017-20228

Flat Assembler 1.71.21 Stack-Based Buffer Overflow ROP

CVSS 8.6 HIGHEPSS 0.2%CWE-787

Vexday Risk Score

41Attention

SSVC decision (CISA)

Attend

PoC available → attend closely

Exploit maturity

Proof of concept

Public proof of concept exists, but not yet automated.

CVSS 8.6EPSS 0.2%KEV nãoPoC públicaNuclei —Metasploit —Patch —

Lifecycle

28 Mar 2026Published on NVD

Recommendation: Plan a near-term fix — a public PoC already exists.

Flat Assembler 1.71.21 contains a stack-based buffer overflow vulnerability that allows local attackers to execute arbitrary code by supplying oversized input to the application. Attackers can craft malicious assembly input exceeding 5895 bytes to overwrite the instruction pointer and execute return-oriented programming chains for shell command execution.

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Affected products

Flatassembler · Flat Assembler

public PoCs found — 1

cve_referencewww.exploit-db.com/exploits/42265unverified

⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.

References

https://www.exploit-db.com/exploits/42265 https://www.vulncheck.com/advisories/flat-assembler-stack-based-buffer-overflow-rop http://www.flatassembler.net