CVE-2021-46989 remediation guide
Linux Linux, linux kernel
In the Linux kernel, the following vulnerability has been resolved: hfsplus: prevent corruption in shrinking truncate I believe there are some issues introduced by commit 31651c607151 ("hfsplus: avoid deadlock on file truncation") HFS+ has extent records which always contains 8 extents. In case the first extent record in catalog file gets full, new ones are allocated from extents overflow file. In case shrinking truncate happens to middle of an extent record which locates in extents overflow file, the logic in hfsplus_file_truncate() was changed so that call to hfs_brec_remove() is not guar...
Identify the affected asset
Confirm whether Linux Linux, linux kernel is installed, record the deployed version and installation path, and identify exposed interfaces.
- Record the product name, package or appliance identifier, and installed version.
- Identify internet-facing, administrative, API, and internal access paths.
- Preserve the pre-change configuration and relevant service logs.
Validate the affected-version match
Compare the deployed version with the affected range: >= 31651c607151f1034cfb57e5a78678bea54c362b < 52dde855663e5db824af51db39b5757d2ef3e28a, >= 31651c607151f1034cfb57e5a78678bea54c362b < c451a6bafb5f422197d31536f82116aed132b72c, >= 31651c607151f1034cfb57e5a78678bea54c362b < adbd8a2a8cc05d9e501f93e5c95c59307874cc99, >= 31651c607151f1034cfb57e5a78678bea54c362b < c477f62db1a0c0ecaa60a29713006ceeeb04b685, >= 31651c607151f1034cfb57e5a78678bea54c362b < 97314e45aa1223a42d60256a62c5d9af54baf446, >= 31651c607151f1034cfb57e5a78678bea54c362b < c3187cf32216313fb316084efac4dab3a8459b1d, >= 4.19, >= 4.19 < 4.19.191, >= 4.20 < 5.4.120, >= 5.5 < 5.10.38, >= 5.11 < 5.11.22, >= 5.12 < 5.12.5, 5.13. Treat incomplete inventory results as unresolved.
Prioritize with independent signals
The CVSS severity warrants an early asset and exposure review. Combine this signal with asset criticality, exposure, compensating controls, and business impact.
Apply supported remediation
Follow the vendor advisory or supported update path. Current fixed-version status: 4.19.191, 5.4.120, 5.10.38, 5.11.22, 5.12.5. Preserve configuration and rollback material before change.
Verify the result
Confirm the resulting version, service health, authentication and access paths, monitoring coverage, and relevant security logs.
- Confirm the expected version and package state.
- Run a functional health check for critical service paths.
- Review authentication, error, application, and security monitoring logs.
- Reassess exposure if the supported fix cannot be applied.
Operational boundary
This page does not replace the vendor advisory, support contract, change-management process, or recovery plan. Do not infer that an asset is unaffected from an incomplete inventory query or a missing fixed-version field.