In the Linux kernel, the following vulnerability has been resolved: hfsplus: fix KMSAN uninit-value issue in __hfsplus_ext_cache_extent() The syzbot… (CVE-2025-40244)
A high severity vulnerability (CVE-2025-40244) in the Linux kernel's HFS+ filesystem driver was identified and resolved. The issue involved an uninitialized value detected by Kernel Memory Sanitizer (KMSAN) in the __hfsplus_ext_cache_extent() function, which could lead to kernel panic and potentially allow an attacker with local privileges to cause denial of service or escalate privileges. The vulnerability was reported by syzbot and fixed in kernel versions after 6.12.0-rc5. No known exploits are reported in the wild.
AI Analysis
Technical Summary
CVE-2025-40244 is a vulnerability in the Linux kernel's HFS+ filesystem implementation where an uninitialized value in the __hfsplus_ext_cache_extent() function was detected by KMSAN. This flaw could cause kernel panic due to use of uninitialized memory, as demonstrated by the detailed kernel stack trace from syzbot. The issue affects local users with write access to HFS+ filesystems and may lead to denial of service or privilege escalation. The vulnerability was fixed in kernel versions following 6.12.0-rc5.
Potential Impact
The vulnerability allows local attackers with write access to HFS+ filesystems to trigger kernel panic or potentially escalate privileges due to use of uninitialized memory. This results in denial of service and compromises system stability and security. No public exploits are known at this time.
Mitigation Recommendations
A fix for this vulnerability has been implemented in Linux kernel versions after 6.12.0-rc5. Users and administrators should update to a kernel version that includes this fix to mitigate the issue. Since this is a kernel-level flaw, applying the official kernel patch or upgrading to a fixed kernel release is the recommended remediation. Patch status is not explicitly confirmed in the input data; check the vendor advisory for current remediation guidance.
In the Linux kernel, the following vulnerability has been resolved: hfsplus: fix KMSAN uninit-value issue in __hfsplus_ext_cache_extent() The syzbot… (CVE-2025-40244)
Description
A high severity vulnerability (CVE-2025-40244) in the Linux kernel's HFS+ filesystem driver was identified and resolved. The issue involved an uninitialized value detected by Kernel Memory Sanitizer (KMSAN) in the __hfsplus_ext_cache_extent() function, which could lead to kernel panic and potentially allow an attacker with local privileges to cause denial of service or escalate privileges. The vulnerability was reported by syzbot and fixed in kernel versions after 6.12.0-rc5. No known exploits are reported in the wild.
CVSS v3.1
Score 7.8high
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2025-40244 is a vulnerability in the Linux kernel's HFS+ filesystem implementation where an uninitialized value in the __hfsplus_ext_cache_extent() function was detected by KMSAN. This flaw could cause kernel panic due to use of uninitialized memory, as demonstrated by the detailed kernel stack trace from syzbot. The issue affects local users with write access to HFS+ filesystems and may lead to denial of service or privilege escalation. The vulnerability was fixed in kernel versions following 6.12.0-rc5.
Potential Impact
The vulnerability allows local attackers with write access to HFS+ filesystems to trigger kernel panic or potentially escalate privileges due to use of uninitialized memory. This results in denial of service and compromises system stability and security. No public exploits are known at this time.
Mitigation Recommendations
A fix for this vulnerability has been implemented in Linux kernel versions after 6.12.0-rc5. Users and administrators should update to a kernel version that includes this fix to mitigate the issue. Since this is a kernel-level flaw, applying the official kernel patch or upgrading to a fixed kernel release is the recommended remediation. Patch status is not explicitly confirmed in the input data; check the vendor advisory for current remediation guidance.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-38x9-7hc9-22jf
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2025-40244"]
- Ecosystems
- []
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
Threat ID: 6a6b72d59c2644c7f8479c78
Added to database: 07/30/2026, 15:50:45 UTC
Last enriched: 07/30/2026, 17:23:08 UTC
Last updated: 08/01/2026, 19:17:55 UTC
Views: 2
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