CVE-2026-64556: perf/core: Detach event groups during remove_on_exec
CVE-2026-64556 is a vulnerability in perf/core: Detach event groups during remove_on_exec, rated Important by Microsoft, with a CVSS 3.1 base score of 7.8 (High). An attacker can exploit it by an attacker with local access, with low privileges and without user interaction. Microsoft has not reported exploitation in the wild. The EPSS model estimates a 0.16% probability of exploitation activity in the next 30 days, higher than 5% of all scored vulnerabilities. Microsoft released the fix on 6 August 2026, outside Patch Tuesday. It affects 1 product in 1 product family (Open Source Software).
Key facts
- CVE ID
- CVE-2026-64556
- Severity
- High CVSS 7.8
- Microsoft severity
- Important
- Exploited in the wild
- No
- Publicly disclosed
- No
- Weakness
- CWE-662
- EPSS
- 0.16% (percentile 5%)
- CISA KEV
- Not listed
- Released
- Last updated
- Patch Tuesday
- July 2026 Patch Tuesday
- Product families
- Open Source Software
CVSS score and vector
Microsoft scores CVE-2026-64556 at 7.8 (temporal 7.1) using CVSS 3.1. Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U
| Metric | Value |
|---|---|
| Attack vector | Local |
| Attack complexity | Low |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality impact | High |
| Integrity impact | High |
| Availability impact | High |
| Exploit code maturity | Unproven |
Affected products (1)
Open Source Software
| Product | Security update | Type | Fixed build | Restart |
|---|---|---|---|---|
| azl3 kernel 6.6.144.1-1 on Azure Linux 3.0 | CBL-Mariner Releases | Security Update | 6.6.145.2-1 | No |
NIST NVD data
- NVD status
- Analyzed
- NVD CVSS
- 7.8 (HIGH)
- NVD weakness
- CWE-662
- Published to NVD
- NVD last modified
Affected configurations (CPE)
| Product | Vulnerable versions |
|---|---|
| linux kernel | from 5.13, before 6.1.191 |
| linux kernel | from 6.2, before 6.6.145 |
| linux kernel | from 6.7, before 6.12.96 |
| linux kernel | from 6.13, before 6.18.39 |
| linux kernel | from 6.19, before 7.1.4 |
| linux kernel 7.2 | all listed versions |
References
- https://git.kernel.org/stable/c/037a3c43edfb597665dd34457cd22b14692f2ba3 (Patch)
- https://git.kernel.org/stable/c/06ccef0434e98058ddae7bcebc901f93d22b7653 (Patch)
- https://git.kernel.org/stable/c/1d3e1102273f09180262496658e7eeed8a5a7b59 (Patch)
- https://git.kernel.org/stable/c/39358e856fb89e62e3c8d7389a2dc4ec33dbe90e (Patch)
- https://git.kernel.org/stable/c/4cdb1b3ab96eb1b7eb70bc5c82fede334bd60df2 (Patch)
- https://git.kernel.org/stable/c/a2d5d3ee7b6e3953114726b1521e62123ab5b043 (Patch)
Revision history
| Version | Date | Description |
|---|---|---|
| 1.0 | Information published. |