CVE-2025-39715: parisc: Revise gateway LWS calls to probe user read access
In the Linux kernel, the following vulnerability has been resolved:
parisc: Revise gateway LWS calls to probe user read access
We use load and stbys,e instructions to trigger memory reference interruptions without writing to memory. Because of the way read access support is implemented, read access interruptions are only triggered at privilege levels 2 and 3. The kernel and gateway page execute at privilege level 0, so this code never triggers a read access interruption. Thus, it is currently possible for user code to execute a LWS compare and swap operation at an address that is read protected at privilege level 3 (PRIVUSER).
Fix this by probing read access rights at privilege level 3 and branching to lwsfault if access isn't allowed.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2025-39715?
CVE-2025-39715 is classified as a moderate severity vulnerability in the Linux kernel.
How do I fix CVE-2025-39715?
To fix CVE-2025-39715, update the Linux kernel to the latest version that addresses this vulnerability.
What systems are affected by CVE-2025-39715?
CVE-2025-39715 affects various versions of the Linux kernel, particularly those utilizing parisc architecture.
What are the potential impacts of CVE-2025-39715?
The potential impacts of CVE-2025-39715 include unauthorized access to memory and possible disruption of system stability.
Has CVE-2025-39715 been disclosed publicly?
Yes, CVE-2025-39715 has been publicly disclosed along with its mitigation details.