Data corruption via signed AFS fetch offsets
Published May 21, 2024 · Updated Aug 5, 2026
Data corruption in the Linux kernel AFS client before 5.14.9 allows local users to receive incorrect file contents from OpenAFS servers. The client selects FS.FetchData from upper offset bits instead of the server's 64-bit-file capability, then sends 2–4 GiB positions in signed 32-bit fields that the server sign-extends. A mounted OpenAFS filesystem, a non-YFS server, and a file in that offset range are required; affected reads return errors or corrupted data.
Summary
What happened
Data corruption in the Linux kernel AFS client before 5.14.9 allows local users to receive incorrect file contents from OpenAFS servers. The client selects FS.FetchData from upper offset bits instead of the server's 64-bit-file capability, then sends 2–4 GiB positions in signed 32-bit fields that the server sign-extends. A mounted OpenAFS filesystem, a non-YFS server, and a file in that offset range are required; affected reads return errors or corrupted data.
The record
- CVE
- CVE-2021-47366
- Published
- May 21, 2024
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-787
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 21, 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=2.6.22
- Affected versionversion=b9b1f8d5930a813879278d0cbfc8c658d6a038dc <b537a3c21775075395af475dcc6ef212fcf29db8
- Affected versionversion=b9b1f8d5930a813879278d0cbfc8c658d6a038dc <e66fc460d6dcf85cf12288e133a081205aebcd97
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
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