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Δ / VULNERABILITY RECORD

CVE-2026-21716.

Source-reported disclosure and enrichment record.

SEVERITY / CVSSLOW / 3.3No severity score in this snapshot.
EXPLOITATION STATUSNot listed in the cached KEV catalogThis does not establish absence of exploitation.
RECORD STATUSMicrosoft vendor recordModified Apr 08, 2026

Disclosure summary

An incomplete fix for CVE-2024-36137 leaves `FileHandle.chmod()` and `FileHandle.chown()` in the promises API without the required permission checks, while their callback-based equivalents (`fs.fchmod()`, `fs.fchown()`) were correctly patched. As a result, code running under `--permission` with restricted `--allow-fs-write` can still use promise-based `FileHandle` methods to modify file permissions and ownership on already-open file descriptors, bypassing the intended write restrictions. This vulnerability affects **20.x, 22.x, 24.x, and 25.x** processes using the Permission Model where `--allow-fs-write` is intentionally restricted.

Source-reported weakness categories

CWE-862

Source-specific records & product guidance

Sources retain their own attribution and scoring. Follow the original record to confirm affected versions, fixed releases, and configuration conditions.

Microsoft Security Updates (CVRF) · 2026-Mar

Open original source · Updated Apr 08, 2026

An incomplete fix for CVE-2024-36137 leaves `FileHandle.chmod()` and `FileHandle.chown()` in the promises API without the required permission checks, while their callback-based equivalents (`fs.fchmod()`, `fs.fchown()`) were correctly patched. As a result, code running under `--permission` with restricted `--allow-fs-write` can still use promise-based `FileHandle` methods to modify file permissions and ownership on already-open file descriptors, bypassing the intended write restrictions. This vulnerability affects **20.x, 22.x, 24.x, and 25.x** processes using the Permission Model where `--allow-fs-write` is intentionally restricted.

Maximum of vendor-reported product scores; products and fixed builds are associations, not a universal affected-version statement.

Microsoft maximum product score: 3.3

VendorProduct / associationVersion / bounds
Microsoft update guideazl3 nodejs24 24.13.0-3 on Azure Linux 3.0 (MSRC status code 3)
Microsoft update guideazl3 nodejs 20.14.0-14 on Azure Linux 3.0 (MSRC status code 3)

Vendor remediation references

  • CBL-Mariner Releases · build 24.14.1-1 · product IDs 21059-17084
  • Vendor guidance · product IDs 21059-17084
  • CBL-Mariner Releases · build 20.14.0-15 · product IDs 21111-17084
  • Vendor guidance · product IDs 21111-17084

Original records & references

PUBLISHED 2026-03-31T21:19:13-04:00
MODIFIED 2026-04-08T21:40:06-04:00
INGESTED 2026-10-08T12:45:08-04:00