Linux: Use After Free
CVE-2023-52469 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 8a27d9d9fc9b5564b8904c3a77a7dea482bfa34e, 8b55b06e737feb2a645b0293ea27e38418876d63, 520e213a0b97b64735a13950e9371e0a5d7a5dc3 as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.29% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to 8a27d9d9fc9b5564b8904c3a77a7dea482bfa34e or 8b55b06e737feb2a645b0293ea27e38418876d63 or 520e213a0b97b64735a13950e9371e0a5d7a5dc3 or b6dcba02ee178282e0d28684d241e0b8462dea6a, whichever matches your release line, or a later version.
- Update Linux Kernel to 4.19.306 or 5.4.268 or 5.10.209 or 5.15.148, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | a2e73f56fa6282481927ec43aa9362c03c2e2104 up to, but not including, 8a27d9d9fc9b5564b8904c3a77a7dea482bfa34e; a2e73f56fa6282481927ec43aa9362c03c2e2104 up to, but not including, 8b55b06e737feb2a645b0293ea27e38418876d63; a2e73f56fa6282481927ec43aa9362c03c2e2104 up to, but not including, 520e213a0b97b64735a13950e9371e0a5d7a5dc3; a2e73f56fa6282481927ec43aa9362c03c2e2104 up to, but not including, b6dcba02ee178282e0d28684d241e0b8462dea6a; a2e73f56fa6282481927ec43aa9362c03c2e2104 up to, but not including, 35fa2394d26e919f63600ce631e6aefc95ec2706; a2e73f56fa6282481927ec43aa9362c03c2e2104 up to, but not including, 95084632a65d5c0d682a83b55935560bdcd2a1e3; a2e73f56fa6282481927ec43aa9362c03c2e2104 up to, but not including, 3426f059eacc33ecc676b0d66539297e1cfafd02; a2e73f56fa6282481927ec43aa9362c03c2e2104 up to, but not including, 28dd788382c43b330480f57cd34cde0840896743; and 1 more ranges | 8a27d9d9fc9b5564b8904c3a77a7dea482bfa34e, 8b55b06e737feb2a645b0293ea27e38418876d63, 520e213a0b97b64735a13950e9371e0a5d7a5dc3, b6dcba02ee178282e0d28684d241e0b8462dea6a, 35fa2394d26e919f63600ce631e6aefc95ec2706, 95084632a65d5c0d682a83b55935560bdcd2a1e3 |
| Linux | Linux Kernel | 4.2.0 up to, but not including, 4.19.306; 4.20.0 up to, but not including, 5.4.268; 5.5.0 up to, but not including, 5.10.209; 5.11.0 up to, but not including, 5.15.148; 5.16.0 up to, but not including, 6.1.75; 6.2.0 up to, but not including, 6.6.14; 6.7.0 up to, but not including, 6.7.2 | 4.19.306, 5.4.268, 5.10.209, 5.15.148, 6.1.75, 6.6.14 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.8 | High | CNA |
| CVSS 3.1 | 7.8 | High | NVD |
Official description
In the Linux kernel, the following vulnerability has been resolved: drivers/amd/pm: fix a use-after-free in kv_parse_power_table When ps allocated by kzalloc equals to NULL, kv_parse_power_table frees adev->pm.dpm.ps that allocated before. However, after the control flow goes through the following call chains: kv_parse_power_table |-> kv_dpm_init |-> kv_dpm_sw_init |-> kv_dpm_fini The adev->pm.dpm.ps is used in the for loop of kv_dpm_fini after its first free in kv_parse_power_table and causes a use-after-free bug.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/28dd788382c43b330480f57cd34cde0840896743
- git.kernel.org/stable/c/3426f059eacc33ecc676b0d66539297e1cfafd02
- git.kernel.org/stable/c/35fa2394d26e919f63600ce631e6aefc95ec2706
- git.kernel.org/stable/c/520e213a0b97b64735a13950e9371e0a5d7a5dc3
- git.kernel.org/stable/c/8a27d9d9fc9b5564b8904c3a77a7dea482bfa34e
- git.kernel.org/stable/c/8b55b06e737feb2a645b0293ea27e38418876d63
- git.kernel.org/stable/c/95084632a65d5c0d682a83b55935560bdcd2a1e3
- git.kernel.org/stable/c/b6dcba02ee178282e0d28684d241e0b8462dea6a
Other references
Recent Use After Free vulnerabilities
- 8.1 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
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