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PatchSiren cyber security CVE debrief

CVE-2026-6068 Nasm CVE debrief

CVE-2026-6068 is a medium-severity memory-safety flaw in NASM’s response file (-@) handling. The issue occurs when a dangling pointer to freed memory is stored in the global depend_file and later dereferenced after the response-file buffer has already been freed. In practical terms, that can lead to data corruption and, depending on how the assembler is used, may create a remote code execution risk. The CVE was published on 2026-04-10 and NVD later modified the record on 2026-05-20.

Vendor
Nasm
Product
Netwide Assembler
CVSS
MEDIUM 6.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-10
Original CVE updated
2026-05-20
Advisory published
2026-04-10
Advisory updated
2026-05-20

Who should care

Teams that build or package software with NASM, especially CI/CD and release engineering environments that process untrusted or externally supplied response files (-@). Security teams should also care if NASM is used in automated pipelines where a crash or memory corruption could affect build integrity.

Technical summary

NVD classifies the flaw as CWE-416 (Use After Free) with CVSS 3.1 vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N. The supplied description says the vulnerability is in response file (-@) processing: a pointer into freed response-file buffer memory is retained in the global depend_file and dereferenced later, after the buffer has been freed. NVD’s CPE data explicitly marks nasm:netwide_assembler:3.02:rc5 as vulnerable.

Defensive priority

Medium, but prioritize quickly in build systems and other environments where NASM processes untrusted inputs or where build integrity is important.

Recommended defensive actions

  • Confirm whether your NASM deployment includes an affected build and whether response files (-@) are used in automated workflows.
  • Upgrade to a fixed NASM release once one is available in your supported distribution or upstream channel; verify package advisories for the exact patched version.
  • Restrict or remove untrusted response-file inputs from build paths until patched.
  • Isolate NASM in a sandboxed or least-privilege build environment to reduce the impact of memory-corruption bugs.
  • Monitor build logs and crash reports for failures around response-file parsing or unexpected assembler instability.
  • Rebuild and revalidate artifacts after remediation to ensure the toolchain is trustworthy.

Evidence notes

This debrief is based on the supplied CVE/NVD corpus only. The core vulnerability statement comes from the provided CVE description: a heap use-after-free in NASM response-file (-@) processing caused by a dangling pointer stored in depend_file after the response-file buffer is freed. NVD metadata in the corpus classifies the issue as CWE-416 and provides the CVSS vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N. The corpus also includes upstream issue-tracker and disclosure-blog references for additional context, but no fixed version details were supplied.

Official resources

Publicly disclosed in the CVE record on 2026-04-10; NVD metadata was updated on 2026-05-20.