CVE-2025-39715
📋 TL;DR
This CVE describes a privilege escalation vulnerability in the Linux kernel's parisc architecture where user code can execute LWS compare-and-swap operations at memory addresses that should be read-protected. The vulnerability affects systems running Linux kernels with parisc architecture support. Attackers could potentially read kernel memory or sensitive data they shouldn't have access to.
💻 Affected Systems
- Linux kernel
📦 What is this software?
Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →⚠️ Risk & Real-World Impact
Worst Case
Privilege escalation allowing user processes to read kernel memory, potentially exposing sensitive data or enabling further exploitation.
Likely Case
Information disclosure where user processes can read protected memory regions, potentially exposing sensitive kernel data or other process memory.
If Mitigated
Minimal impact if proper access controls and kernel hardening are in place, though information disclosure risk remains.
🎯 Exploit Status
Exploitation requires local access and knowledge of parisc architecture specifics. No public exploits known at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel trees (commits referenced in CVE)
Vendor Advisory: https://git.kernel.org/stable/c/8bccf47adbf658293528e86960e6d6f736b1c9f7
Restart Required: Yes
Instructions:
1. Update to a patched Linux kernel version containing the fix commits. 2. Reboot the system to load the new kernel. 3. Verify the fix is applied by checking kernel version or testing the vulnerability.
🔧 Temporary Workarounds
Restrict user access
allLimit shell access to trusted users only on parisc systems
Review and restrict user accounts with shell access
Implement strict access controls
🧯 If You Can't Patch
- Implement strict user access controls and monitoring on parisc systems
- Consider migrating critical workloads to unaffected architectures if possible
🔍 How to Verify
Check if Vulnerable:
Check if running on parisc architecture and if kernel version contains the vulnerable code. Use: 'uname -m' to check architecture and 'uname -r' for kernel version.Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated to one containing the fix commits. Check kernel changelog or verify the specific commit is present.📡 Detection & Monitoring
Log Indicators:
- Kernel logs showing memory access violations
- System logs showing privilege escalation attempts
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
Search for kernel panic logs or privilege escalation attempts on parisc systems🔗 References
- https://git.kernel.org/stable/c/8bccf47adbf658293528e86960e6d6f736b1c9f7
- https://git.kernel.org/stable/c/9b6af875baba9c4679b55f4561e201485451305f
- https://git.kernel.org/stable/c/bc0a24c24ceebabb5ba65900e332233d79e625e6
- https://git.kernel.org/stable/c/e8b496c52aa0c6572d88db7cab85aeea6f9c194d
- https://git.kernel.org/stable/c/f6334f4ae9a4e962ba74b026e1d965dfdf8cbef8
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
