Kernel crash via zero-reference Btrfs extent
Published Sep 18, 2024 · Updated Aug 5, 2026
Denial of service in affected Linux kernels allows local users to crash the host by exercising a Btrfs extent with zero references. In fs/btrfs/extent-tree.c, btrfs_lookup_extent_info() passes a zero extent reference count to BUG_ON(), triggering a kernel panic instead of returning an error. Reaching the path requires local access to attach or loop-mount a crafted Btrfs image and drive it with file writes or subvolume deletion; the bounded consequence is a host outage.
Summary
What happened
Denial of service in affected Linux kernels allows local users to crash the host by exercising a Btrfs extent with zero references. In fs/btrfs/extent-tree.c, btrfs_lookup_extent_info() passes a zero extent reference count to BUG_ON(), triggering a kernel panic instead of returning an error. Reaching the path requires local access to attach or loop-mount a crafted Btrfs image and drive it with file writes or subvolume deletion; the bounded consequence is a host outage.
The record
- CVE
- CVE-2024-46751
- Published
- Sep 18, 2024
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 18, 2024CVE publishedPublication date reported by the CVE source.
- Aug 5, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2.6.31
- Affected versionversion=5d4f98a28c7d334091c1b7744f48a1acdd2a4ae0 <18eb53a2734ff61b9a72c4fef5db7b38cb48ae16
- Affected versionversion=5d4f98a28c7d334091c1b7744f48a1acdd2a4ae0 <28cb13f29faf6290597b24b728dc3100c019356f
- Affected versionversion=5d4f98a28c7d334091c1b7744f48a1acdd2a4ae0 <3cfec712a439c5c5f5c718c5c669ee41a898f776
- Affected versionversion=5d4f98a28c7d334091c1b7744f48a1acdd2a4ae0 <9c309d2434abbe880712af7e60da9ead8b6703fe
- Affected versionversion=5d4f98a28c7d334091c1b7744f48a1acdd2a4ae0 <d64807ded1b6054f066e03d8add6d920f3db9e5d
- Affected versionversion=5d4f98a28c7d334091c1b7744f48a1acdd2a4ae0 <ef9a8b73c8b60b27d9db4787e624a3438ffe8428
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo