Local privilege escalation via shared-fragment decryption
Published May 11, 2026 · Updated May 11, 2026
Out-of-bounds write in Linux Kernel 5.3 and later before branch-specific fixes allows local users to gain root privileges via RxRPC packets. The DATA and RESPONSE handlers decrypt non-cloned socket buffers in place without first unsharing externally owned paged fragments, binding those pages into the crypto scatterlist. Low-privileged local code can create splice-backed packets without a race or user interaction; exploitation requires the RxRPC stack and can corrupt readable page-cache files.
Summary
What happened
Out-of-bounds write in Linux Kernel 5.3 and later before branch-specific fixes allows local users to gain root privileges via RxRPC packets. The DATA and RESPONSE handlers decrypt non-cloned socket buffers in place without first unsharing externally owned paged fragments, binding those pages into the crypto scatterlist. Low-privileged local code can create splice-backed packets without a race or user interaction; exploitation requires the RxRPC stack and can corrupt readable page-cache files.
The record
- CVE
- CVE-2026-43500
- Published
- May 11, 2026
- Updated
- May 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-787, CWE-123, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 11, 2026CVE publishedPublication date reported by the CVE source.
- May 11, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=5.3
- Affected versionversion=d0d5c0cd1e711c98703f3544c1e6fc1372898de5 <3eae0f4f9f7206a4801efa5e0235c25bbd5a412c
- Affected versionversion=d0d5c0cd1e711c98703f3544c1e6fc1372898de5 <aa54b1d27fe0c2b78e664a34fd0fdf7cd1960d71
- Affected versionversion=d0d5c0cd1e711c98703f3544c1e6fc1372898de5 <d45179f8795222ce858770dc619abe51f9d24411
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
- Dirty Frag RxRPC Page-Cache Write exploitfunctional · demonstrated
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
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