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TI-2026-05321 Aliases CVE-2026-6069GHSA-pfc2-7mmr-x54w

Out-of-bounds write in NASM

Priority HIGH 72CWE-787Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-787 and the CVSS impact.

Summary

NASM’s disasm() function contains a stack based buffer overflow when formatting disassembly output, allowing an attacker triggered out-of-bounds write when `slen` exceeds the buffer capacity.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0045 39th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
NASMNASMnasm-3.02rc5—No fix listedCNA
  • NASM VendorNASM Affected nasm-3.02rc5 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:nasm:netwide_assembler:3.02:rc5:*:*:*:*:*:*3.02 rc5VulnerableNASM
  • cpe:2.3:a:nasm:netwide_assembler:3.02:rc5:*:*:*:*:*:* Versions 3.02 rc5 Vulnerable ·NASM

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-6069
  2. 2026-10-03 Alias added: GHSA-pfc2-7mmr-x54w

References

Exploit 1

  • TI-2026-05320 Use after free in NASM CVSS 3.1CRITICAL 9.6
  • TI-2026-05319 Out-of-bounds write in NASM CVSS 3.1HIGH 7.5
  • TI-2004-01165 Buffer overflow in the error function in preproc.c for NASM 0.98.38 1.2 allows attackers… CVSS 2.0HIGH 10.0
  • TI-2023-20017 Stack-based buffer over-read in disasm in nasm 2.16 allows attackers to cause a denial of service (crash). CVSS 3.1MEDIUM 5.5
  • TI-2023-20016 Stack-based buffer over-read in function disasm in nasm 2.16 allows attackers to cause a denial of service. CVSS 3.1MEDIUM 5.5
  • TI-2023-20014 Null pointer dereference in ieee_write_file in nasm 2.16rc0 allows attackers to cause a denial of service (crash). CVSS 3.1MEDIUM 5.5
See all 74 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences