Linux: Use After Free
CVE-2026-23216 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 ba684191437380a07b27666eb4e72748be1ea201, 8518f072fc92921418cd9ed4268dd4f3e9a8fd75, 275016a551ba1a068a3bd6171b18611726b67110 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 0.14% 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 ba684191437380a07b27666eb4e72748be1ea201 or 8518f072fc92921418cd9ed4268dd4f3e9a8fd75 or 275016a551ba1a068a3bd6171b18611726b67110 or 73b487d44bf4f92942629d578381f89c326ff77f, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.10.250 or 5.15.200 or 6.1.163 or 6.6.124, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | e48354ce078c079996f89d715dfa44814b4eba01 up to, but not including, ba684191437380a07b27666eb4e72748be1ea201; e48354ce078c079996f89d715dfa44814b4eba01 up to, but not including, 8518f072fc92921418cd9ed4268dd4f3e9a8fd75; e48354ce078c079996f89d715dfa44814b4eba01 up to, but not including, 275016a551ba1a068a3bd6171b18611726b67110; e48354ce078c079996f89d715dfa44814b4eba01 up to, but not including, 73b487d44bf4f92942629d578381f89c326ff77f; e48354ce078c079996f89d715dfa44814b4eba01 up to, but not including, 48fe983e92de2c59d143fe38362ad17ba23ec7f3; e48354ce078c079996f89d715dfa44814b4eba01 up to, but not including, 3835e49e146a4e6e7787b29465f1a23379b6ec44; e48354ce078c079996f89d715dfa44814b4eba01 up to, but not including, 9411a89e9e7135cc459178fa77a3f1d6191ae903; 3.1 | ba684191437380a07b27666eb4e72748be1ea201, 8518f072fc92921418cd9ed4268dd4f3e9a8fd75, 275016a551ba1a068a3bd6171b18611726b67110, 73b487d44bf4f92942629d578381f89c326ff77f, 48fe983e92de2c59d143fe38362ad17ba23ec7f3, 3835e49e146a4e6e7787b29465f1a23379b6ec44 |
| Linux | Linux Kernel | 3.1 up to, but not including, 5.10.250; 5.11 up to, but not including, 5.15.200; 5.16 up to, but not including, 6.1.163; 6.2 up to, but not including, 6.6.124; 6.7 up to, but not including, 6.12.70; 6.13 up to, but not including, 6.18.10; 6.19 | 5.10.250, 5.15.200, 6.1.163, 6.6.124, 6.12.70, 6.18.10 |
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: scsi: target: iscsi: Fix use-after-free in iscsit_dec_conn_usage_count() In iscsit_dec_conn_usage_count(), the function calls complete() while holding the conn->conn_usage_lock. As soon as complete() is invoked, the waiter (such as iscsit_close_connection()) may wake up and proceed to free the iscsit_conn structure. If the waiter frees the memory before the current thread reaches spin_unlock_bh(), it results in a KASAN slab-use-after-free as the function attempts to release a lock within the already-freed connection structure. Fix this by releasing the spinlock before calling complete().
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: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/275016a551ba1a068a3bd6171b18611726b67110
- git.kernel.org/stable/c/3835e49e146a4e6e7787b29465f1a23379b6ec44
- git.kernel.org/stable/c/48fe983e92de2c59d143fe38362ad17ba23ec7f3
- git.kernel.org/stable/c/73b487d44bf4f92942629d578381f89c326ff77f
- git.kernel.org/stable/c/8518f072fc92921418cd9ed4268dd4f3e9a8fd75
- git.kernel.org/stable/c/9411a89e9e7135cc459178fa77a3f1d6191ae903
- git.kernel.org/stable/c/ba684191437380a07b27666eb4e72748be1ea201
Recent Use After Free vulnerabilities
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- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
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