Local denial of service via fatal-signal retry loop
Published Aug 15, 2026 · Updated Aug 15, 2026
Denial of service in Linux before 7.2 allows local users to hang coredump processing by signaling a blocked 9p client RPC. In p9_client_rpc, the P9_TFLUSH retry path clears TIF_SIGPENDING before waiting again, so a pending fatal signal is lost and the task repeatedly sleeps. The condition requires a 9p fd transport with no peer and a fatal signal; affected stable kernels can instead leave a zombie process and delay shutdown.
Summary
What happened
Denial of service in Linux before 7.2 allows local users to hang coredump processing by signaling a blocked 9p client RPC. In p9_client_rpc, the P9_TFLUSH retry path clears TIF_SIGPENDING before waiting again, so a pending fatal signal is lost and the task repeatedly sleeps. The condition requires a 9p fd transport with no peer and a fatal signal; affected stable kernels can instead leave a zombie process and delay shutdown.
The record
- CVE
- CVE-2026-72166
- Published
- Aug 15, 2026
- Updated
- Aug 15, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-835, T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 15, 2026CVE publishedPublication date reported by the CVE source.
- Aug 15, 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?
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- Affected versionversion=2.6.28
- Affected versionversion=91b8534fa8f5e01f249b1bf8df0a2540053549ad <378481cc60a937ef8ea4ef6e4f95f0dbc4e21414
- Affected versionversion=91b8534fa8f5e01f249b1bf8df0a2540053549ad <4f621ae3a2d99b0bac50e8d66cbf7f68323c01e8
- Affected versionversion=91b8534fa8f5e01f249b1bf8df0a2540053549ad <6b4f48728faa8bb514368f7eacda05565dea8696
- Affected versionversion=91b8534fa8f5e01f249b1bf8df0a2540053549ad <823886a1b089b49bcd349bc8bd3417b7910cd1ac
- Affected versionversion=91b8534fa8f5e01f249b1bf8df0a2540053549ad <a8874c34c4a973f9922908a4b8be1d1278f01e42
- Affected versionversion=91b8534fa8f5e01f249b1bf8df0a2540053549ad <dc892cbb1e4341d427b1f940ebd6abd69bf8e479
- Affected versionversion=91b8534fa8f5e01f249b1bf8df0a2540053549ad <f62a1f245a71680033260a6f6d74011cc3acb3cd
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What is affected?
Published CVSS scores
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Attacks
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