CVE-2022-49873

MEDIUMCVSS 5.5/10EPSS 0.18%

Last modified

CVE-2022-49873 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. In the Linux kernel, the following vulnerability has been resolved: bpf: Fix wrong reg type conversion in release_reference() Some helper functions will allocate memory. To avoid memory leaks, the verifier requires the eBPF program to release these memories by calling the corresponding helper functions. When a resource is released, all pointer registers corresponding to the resource should be invalidated. EPSS estimates a 0.18% chance of exploitation in the next 30 days.

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix wrong reg type conversion in release_reference() Some helper functions will allocate memory. To avoid memory leaks, the verifier requires the eBPF program to release these memories by calling the corresponding helper functions. When a resource is released, all pointer registers corresponding to the resource should be invalidated. The verifier use release_references() to do this job, by apply __mark_reg_unknown() to each relevant register. It will give these registers the type of SCALAR_VALUE. A register that will contain a pointer value at runtime, but of type SCALAR_VALUE, which may allow the unprivileged user to get a kernel pointer by storing this register into a map. Using __mark_reg_not_init() while NOT allow_ptr_leaks can mitigate this problem.

Metrics

CVSS 3.1
5.5/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability
0.18%

7.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersionsUpdate
LinuxLinux Kernel>= 4.20, < 5.10.155
LinuxLinux Kernel>= 5.11, < 5.15.79
LinuxLinux Kernel>= 5.16, < 6.0.9
LinuxLinux Kernel6.1Rc1

References

Timeline

Published
Last Modified
Status
Modified

Frequently Asked Questions

What is CVE-2022-49873?
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix wrong reg type conversion in release_reference() Some helper functions will allocate memory. To avoid memory leaks, the verifier requires the eBPF program to release these memories by calling the corresponding helper functions. When a resource is released, all pointer registers corresponding to the resource should be invalidated. The verifier use release_references() to do this job, by apply __mark_reg_unknown() to each relevant register. It will give these registers the type of SCALAR_VALUE. A register that will contain a pointer value at runtime, but of type SCALAR_VALUE, which may allow the unprivileged user to get a kernel pointer by storing this register into a map. Using __mark_reg_not_init() while NOT allow_ptr_leaks can mitigate this problem.
How severe is CVE-2022-49873?
CVE-2022-49873 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.18% probability of exploitation in the next 30 days.
How do I fix CVE-2022-49873?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2022-49873?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST