Microsoft security update for CVE-2026-5958
🔗 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-2026-5958. This page also shows what EchelonGraph holds for CVE-2026-5958, 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 products5
- azl3 sed 4.9-1 on Azure Linux 3.0
- azl3 sed 4.9-2 on Azure Linux 3.0
- cbl2 sed 4.8-3
- cbl2 sed 4.8-3 on CBL Mariner 2.0
- cbl2 sed 4.8-3 on CBL-Mariner 2.0
✅ 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 | 4.9-2 |
| — | Security Update | — |
🧭 EchelonGraph on CVE-2026-5958
- EchelonGraph score
- 2.1 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
When sed is invoked with both -i (in-place edit) and --follow-symlinks, the function open_next_file() performs two separate, non-atomic filesystem operations on the same path: 1. resolves symlink to its target and stores the resolved path for determining when output is written, 2. opens the original symlink path (not the resolved one) to read the file. Between these two calls there is a race window. If an attacker atomically replaces the symlink with a different target during that window, sed will: read content from the new (attacker-chosen) symlink target and write the processed result to the path recorded in step 1. This can lead to arbitrary file overwrite with attacker-controlled content in the context of the sed process. This issue was fixed in version 4.10.
Published by CERT.PL, the CVE Numbering Authority that assigned CVE-2026-5958, 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).