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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
CRITICAL 9.6
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-10
Original CVE updated
2026-05-26
Advisory published
2026-04-10
Advisory updated
2026-05-26

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.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-6068 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-6068

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-6068 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-6068

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.