Microsoft security update for CVE-2026-21716 — azl3
🔗 CVE IDs covered (1)
📋 Microsoft's advisory
EchelonGraph does not copy Microsoft's advisory page: its FAQ and remediation text are not shown here. Read the advisory on https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21716. This page also shows what EchelonGraph holds for CVE-2026-21716, with the description from its CVE record, which the CVE Numbering Authority that assigned the CVE wrote: for a CVE Microsoft assigned, often in the words of Microsoft's own advisory.
🎯 Affected products2
- azl3 nodejs 20.14.0-14 on Azure Linux 3.0
- azl3 nodejs24 24.13.0-3 on Azure Linux 3.0
✅ Updates Microsoft lists: 2 updates
2 rows: one per KB article or update, update type and fixed build. Their details are on Microsoft's advisory.
| KB article | Update | Fixed build |
|---|---|---|
| — | Security Update | 24.14.1-1 |
| — | Security Update | 20.14.0-15 |
🧭 EchelonGraph on CVE-2026-21716
- EchelonGraph score
- 3.3 LOW
- CISA KEV
- Not listed
- Fix status
- A fix is available — apply it.
Description from the CVE record (CVE.org), as published by its numbering authority
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.
Published by HackerOne, the CVE Numbering Authority that assigned CVE-2026-21716, in its CVE record at CVE.org; reused under the CVE Program's Terms of Use (its licence and MITRE's copyright notice are in our Terms of Service).