Linux: Use After Free
CVE-2023-53145 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 6c3653627397a0d6eab19b20a59423e118985a6b, 3efcbf25e5ab4d4ad1b7e6ba0869ff85540e3f6e, a6650d27ab2c12a8ee750f396edb5ac8b4558b2e 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 0.19% 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 6c3653627397a0d6eab19b20a59423e118985a6b or 3efcbf25e5ab4d4ad1b7e6ba0869ff85540e3f6e or a6650d27ab2c12a8ee750f396edb5ac8b4558b2e or 746b363bef41cc159c051c47f9e30800bc6b520d, whichever matches your release line, or a later version.
- Update Linux Kernel to 4.14.326 or 4.19.295 or 5.4.257 or 5.10.195, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | ddbaf13e3609442b64abb931ac21527772d87980 up to, but not including, 6c3653627397a0d6eab19b20a59423e118985a6b; ddbaf13e3609442b64abb931ac21527772d87980 up to, but not including, 3efcbf25e5ab4d4ad1b7e6ba0869ff85540e3f6e; ddbaf13e3609442b64abb931ac21527772d87980 up to, but not including, a6650d27ab2c12a8ee750f396edb5ac8b4558b2e; ddbaf13e3609442b64abb931ac21527772d87980 up to, but not including, 746b363bef41cc159c051c47f9e30800bc6b520d; ddbaf13e3609442b64abb931ac21527772d87980 up to, but not including, a5c2a467e9e789ae0891de55b766daac52e3b7b3; ddbaf13e3609442b64abb931ac21527772d87980 up to, but not including, 179c65828593aff1f444e15debd40a477cb23cf4; ddbaf13e3609442b64abb931ac21527772d87980 up to, but not including, 73f7b171b7c09139eb3c6a5677c200dc1be5f318; 2.6.24 | 6c3653627397a0d6eab19b20a59423e118985a6b, 3efcbf25e5ab4d4ad1b7e6ba0869ff85540e3f6e, a6650d27ab2c12a8ee750f396edb5ac8b4558b2e, 746b363bef41cc159c051c47f9e30800bc6b520d, a5c2a467e9e789ae0891de55b766daac52e3b7b3, 179c65828593aff1f444e15debd40a477cb23cf4 |
| Linux | Linux Kernel | before 4.14.326; 4.15 up to, but not including, 4.19.295; 4.20 up to, but not including, 5.4.257; 5.5 up to, but not including, 5.10.195; 5.11 up to, but not including, 5.15.131; 5.16 up to, but not including, 6.1.52; 6.2 up to, but not including, 6.3; 6.3 | 4.14.326, 4.19.295, 5.4.257, 5.10.195, 5.15.131, 6.1.52 |
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.
Official description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btsdio: fix use after free bug in btsdio_remove due to race condition In btsdio_probe, the data->work is bound with btsdio_work. It will be started in btsdio_send_frame. If the btsdio_remove runs with a unfinished work, there may be a race condition that hdev is freed but used in btsdio_work. Fix it by canceling the work before do cleanup in btsdio_remove.
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/179c65828593aff1f444e15debd40a477cb23cf4
- git.kernel.org/stable/c/3efcbf25e5ab4d4ad1b7e6ba0869ff85540e3f6e
- git.kernel.org/stable/c/6c3653627397a0d6eab19b20a59423e118985a6b
- git.kernel.org/stable/c/73f7b171b7c09139eb3c6a5677c200dc1be5f318
- git.kernel.org/stable/c/746b363bef41cc159c051c47f9e30800bc6b520d
- git.kernel.org/stable/c/a5c2a467e9e789ae0891de55b766daac52e3b7b3
- git.kernel.org/stable/c/a6650d27ab2c12a8ee750f396edb5ac8b4558b2e
Recent Use After Free vulnerabilities
- 7.8 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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