Answer in brief
CVE-2025-21863 records a High severity (CVSS 7.8) vulnerability in io_uring: prevent opcode speculation. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=d3656344fea0339fb0365c8df4d2beba4e0089cd <87e9eef43c758da267f6332678058a79764c7eba || >=d3656344fea0339fb0365c8df4d2beba4e0089cd <18eae8420081ef8e043ad455937bfb470ef08607 || >=d3656344fea0339fb0365c8df4d2beba4e0089cd <d261ead565a080e3411b0dd04e6d58a52471cac8 || >=d3656344fea0339fb0365c8df4d2beba4e0089cd <b9826e3b26ec031e9063f64a7c735449c43955e4 || >=d3656344fea0339fb0365c8df4d2beba4e0089cd <506b9b5e8c2d2a411ea8fe361333f5081c56d23a || >=d3656344fea0339fb0365c8df4d2beba4e0089cd <fdbfd52bd8b85ed6783365ff54c82ab7067bd61b || >=d3656344fea0339fb0365c8df4d2beba4e0089cd <1e988c3fe1264708f4f92109203ac5b1d65de50b | 87e9eef43c758da267f6332678058a79764c7eba, 18eae8420081ef8e043ad455937bfb470ef08607, d261ead565a080e3411b0dd04e6d58a52471cac8, b9826e3b26ec031e9063f64a7c735449c43955e4, 506b9b5e8c2d2a411ea8fe361333f5081c56d23a, fdbfd52bd8b85ed6783365ff54c82ab7067bd61b, 1e988c3fe1264708f4f92109203ac5b1d65de50b |
| Linux/Linuxgeneric | 5.6 | Not reported |
Published upstream
Mar 12, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jun 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 19, 2026
In the Linux kernel, the following vulnerability has been resolved: io_uring: prevent opcode speculation sqe->opcode is used for different tables, make sure we santitise it against speculations.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2025-21863 records a High severity (CVSS 7.8) vulnerability in io_uring: prevent opcode speculation. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=d3656344fea0339fb0365c8df4d2beba4e0089cd <87e9eef43c758da267f6332678058a79764c7eba || >=d3656344fea0339fb0365c8df4d2beba4e0089cd <18eae8420081ef8e043ad455937bfb470ef08607 || >=d3656344fea0339fb0365c8df4d2beba4e0089cd <d261ead565a080e3411b0dd04e6d58a52471cac8 || >=d3656344fea0339fb0365c8df4d2beba4e0089cd <b9826e3b26ec031e9063f64a7c735449c43955e4 || >=d3656344fea0339fb0365c8df4d2beba4e0089cd <506b9b5e8c2d2a411ea8fe361333f5081c56d23a || >=d3656344fea0339fb0365c8df4d2beba4e0089cd <fdbfd52bd8b85ed6783365ff54c82ab7067bd61b || >=d3656344fea0339fb0365c8df4d2beba4e0089cd <1e988c3fe1264708f4f92109203ac5b1d65de50b | 87e9eef43c758da267f6332678058a79764c7eba, 18eae8420081ef8e043ad455937bfb470ef08607, d261ead565a080e3411b0dd04e6d58a52471cac8, b9826e3b26ec031e9063f64a7c735449c43955e4, 506b9b5e8c2d2a411ea8fe361333f5081c56d23a, fdbfd52bd8b85ed6783365ff54c82ab7067bd61b, 1e988c3fe1264708f4f92109203ac5b1d65de50b |
| Linux/Linuxgeneric | 5.6 | Not reported |
Published upstream
Mar 12, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jun 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 19, 2026
In the Linux kernel, the following vulnerability has been resolved: io_uring: prevent opcode speculation sqe->opcode is used for different tables, make sure we santitise it against speculations.
Quoted source text, attributed separately from HOL analysis.