CVE-2022-49873
What it is
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.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-704
- Record status
- Modified
Affected
- Linux Kernel < 5.10.155
- Linux Kernel < 5.15.79
- Linux Kernel < 6.0.9
- Linux Kernel 6.1
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Fix and advisories
- https://git.kernel.org/stable/c/466ce46f251dfb259a8cbaa895ab9edd6fb56240
- https://git.kernel.org/stable/c/ae5ccad6c711db0f2ca1231be051935dd128b8f5
- https://git.kernel.org/stable/c/cedd4f01f67be94735f15123158f485028571037
- https://git.kernel.org/stable/c/f1db20814af532f85e091231223e5e4818e8464b