CVE-2025-39694: s390/sclp: Fix SCCB present check
In the Linux kernel, the following vulnerability has been resolved:
s390/sclp: Fix SCCB present check
Tracing code called by the SCLP interrupt handler contains early exits if the SCCB address associated with an interrupt is NULL. This check is performed after physical to virtual address translation.
If the kernel identity mapping does not start at address zero, the resulting virtual address is never zero, so that the NULL checks won't work. Subsequently this may result in incorrect accesses to the first page of the identity mapping.
Fix this by introducing a function that handles the NULL case before address translation.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 6.1.176-1Fixed in 6.1.190-1Fixed in 6.12.107-1Fixed in 6.12.113-1Fixed in 7.2.12-1Fixed in 7.2.13-1
Event History
Frequently Asked Questions
What is the severity of CVE-2025-39694?
CVE-2025-39694 has a moderate severity rating due to its potential impact on system reliability during SCLP interrupts.
How do I fix CVE-2025-39694?
To fix CVE-2025-39694, you should update the Linux kernel to the latest stable version that includes the patch for this vulnerability.
Which versions of the Linux kernel are affected by CVE-2025-39694?
CVE-2025-39694 affects certain versions of the Linux kernel prior to the release that includes the fix for this issue.
Is CVE-2025-39694 exploitable remotely?
CVE-2025-39694 is not directly exploitable remotely as it pertains to internal handling of SCLP interrupts.
What systems are primarily affected by CVE-2025-39694?
CVE-2025-39694 primarily affects systems running the Linux kernel on s390 architecture.