CVE-2022-49955
BaseFortify
Publication date: 2025-06-18
Last updated on: 2025-11-14
Assigner: kernel.org
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | 6.0 |
| linux | linux_kernel | 6.0 |
| linux | linux_kernel | 6.0 |
| linux | linux_kernel | From 5.15.160 (inc) to 5.16 (inc) |
| linux | linux_kernel | From 5.15.160 (inc) to 5.16 (inc) |
| linux | linux_kernel | From 5.15.160 (inc) to 5.16 (inc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-476 | The product dereferences a pointer that it expects to be valid but is NULL. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability involves improper handling of the Machine State Register (MSR) Hypervisor bit (MSR[HV]) when entering the Run-Time Abstraction Services (RTAS) firmware on IBM Cell machines running Linux. Due to recent changes in MSR handling, the kernel crashes because it tries to execute invalid instructions, leading to a kernel oops and potential system instability. The issue arises because Linux runs with MSR[HV] set and uses RTAS provided by SLOF, but the MSR[HV] bit was not correctly copied into the RTAS context, causing faults. The fix involves copying the MSR[HV] bit from the current MSR value into the RTAS MSR value to prevent these crashes.
How can this vulnerability impact me? :
This vulnerability can cause kernel crashes on IBM Cell machines running Linux, leading to system instability and potential denial of service. The kernel may attempt to execute invalid instructions, resulting in a crash (kernel oops) that disrupts normal operation. This can affect system reliability and availability.
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability manifests as kernel crashes on IBM Cell machines with error messages indicating kernel instruction fetch faults and bad area access, as shown in the example trace. Detection involves monitoring system logs (e.g., dmesg or /var/log/kern.log) for such kernel oops or crash messages referencing RTAS and MSR handling errors. Specific commands to check logs include: 'dmesg | grep -i rtas' or 'journalctl -k | grep -i rtas'.
What immediate steps should I take to mitigate this vulnerability?
The vulnerability is fixed by updating the Linux kernel to a version that includes the patch correcting RTAS MSR[HV] handling for IBM Cell machines. Immediate mitigation involves applying the kernel update that contains this fix. There are no other specific mitigation steps mentioned.