Linux: Use After Free
CVE-2023-53106 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 2156490c4b7cacda9a18ec99929940b8376dc0e3, 3405eb641dafcc8b28d174784b203c1622c121bf, b0c202a8dc63008205a5d546559736507a9aae66 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 0.21% 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 2156490c4b7cacda9a18ec99929940b8376dc0e3 or 3405eb641dafcc8b28d174784b203c1622c121bf or b0c202a8dc63008205a5d546559736507a9aae66 or 43aa468df246175207a7d5d7d6d31b231f15b49c, whichever matches your release line, or a later version.
- Update Linux Kernel to 4.14.311 or 4.19.279 or 5.4.238 or 5.10.176, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 35630df68d6030daf12dde12ed07bbe26324e6ac up to, but not including, 2156490c4b7cacda9a18ec99929940b8376dc0e3; 35630df68d6030daf12dde12ed07bbe26324e6ac up to, but not including, 3405eb641dafcc8b28d174784b203c1622c121bf; 35630df68d6030daf12dde12ed07bbe26324e6ac up to, but not including, b0c202a8dc63008205a5d546559736507a9aae66; 35630df68d6030daf12dde12ed07bbe26324e6ac up to, but not including, 43aa468df246175207a7d5d7d6d31b231f15b49c; 35630df68d6030daf12dde12ed07bbe26324e6ac up to, but not including, 84dd9cc34014e3a3dcce0eb6d54b8a067e97676b; 35630df68d6030daf12dde12ed07bbe26324e6ac up to, but not including, 5e331022b448fbc5e76f24349cd0246844dcad25; 35630df68d6030daf12dde12ed07bbe26324e6ac up to, but not including, f589e5b56c562d99ea74e05b1c3f0eab78aa17a3; 35630df68d6030daf12dde12ed07bbe26324e6ac up to, but not including, 5000fe6c27827a61d8250a7e4a1d26c3298ef4f6; and 1 more ranges | 2156490c4b7cacda9a18ec99929940b8376dc0e3, 3405eb641dafcc8b28d174784b203c1622c121bf, b0c202a8dc63008205a5d546559736507a9aae66, 43aa468df246175207a7d5d7d6d31b231f15b49c, 84dd9cc34014e3a3dcce0eb6d54b8a067e97676b, 5e331022b448fbc5e76f24349cd0246844dcad25 |
| Linux | Linux Kernel | 3.17 up to, but not including, 4.14.311; 4.15 up to, but not including, 4.19.279; 4.20 up to, but not including, 5.4.238; 5.5 up to, but not including, 5.10.176; 5.11 up to, but not including, 5.15.104; 5.16 up to, but not including, 6.1.21; 6.2 up to, but not including, 6.2.8; 6.3 | 4.14.311, 4.19.279, 5.4.238, 5.10.176, 5.15.104, 6.1.21 |
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: nfc: st-nci: Fix use after free bug in ndlc_remove due to race condition This bug influences both st_nci_i2c_remove and st_nci_spi_remove. Take st_nci_i2c_remove as an example. In st_nci_i2c_probe, it called ndlc_probe and bound &ndlc->sm_work with llt_ndlc_sm_work. When it calls ndlc_recv or timeout handler, it will finally call schedule_work to start the work. When we call st_nci_i2c_remove to remove the driver, there may be a sequence as follows: Fix it by finishing the work before cleanup in ndlc_remove CPU0 CPU1 |llt_ndlc_sm_work st_nci_i2c_remove | ndlc_remove | st_nci_remove | nci_free_device| kfree(ndev) | //free ndlc->ndev | |llt_ndlc_rcv_queue |nci_recv_frame |//use ndlc->ndev
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.
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/2156490c4b7cacda9a18ec99929940b8376dc0e3
- git.kernel.org/stable/c/3405eb641dafcc8b28d174784b203c1622c121bf
- git.kernel.org/stable/c/43aa468df246175207a7d5d7d6d31b231f15b49c
- git.kernel.org/stable/c/5000fe6c27827a61d8250a7e4a1d26c3298ef4f6
- git.kernel.org/stable/c/5e331022b448fbc5e76f24349cd0246844dcad25
- git.kernel.org/stable/c/84dd9cc34014e3a3dcce0eb6d54b8a067e97676b
- git.kernel.org/stable/c/b0c202a8dc63008205a5d546559736507a9aae66
- git.kernel.org/stable/c/f589e5b56c562d99ea74e05b1c3f0eab78aa17a3
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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