Linux Kernel: NULL Pointer Dereference
CVE-2023-28466 is a high-severity NULL pointer dereference vulnerability in Linux Kernel from Linux, with a CVSS 3.1 base score of 7.0 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 5.10.177, 5.15.105, 6.1.20 as the first without the flaw, so updating Linux Kernel to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.27% 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 Kernel to 5.10.177 or 5.15.105 or 6.1.20 or 6.2.7, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux Kernel | 4.13 through 5.4.240; 5.5 up to, but not including, 5.10.177; 5.11 up to, but not including, 5.15.105; 5.16 up to, but not including, 6.1.20; 6.2 up to, but not including, 6.2.7 | 5.10.177, 5.15.105, 6.1.20, 6.2.7 |
| NetApp | H300s | Not specified in the record | Not stated |
| NetApp | H410c | Not specified in the record | Not stated |
| NetApp | H410s | Not specified in the record | Not stated |
| NetApp | H500s | Not specified in the record | Not stated |
| NetApp | H700s | Not specified in the record | Not stated |
| Debian | Debian Linux | 10.0 | Not stated |
Version data comes from NVD's product matching. 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
- HighSuccess depends on conditions outside the attacker's control.
- 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:H/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.0 | High | NVD |
| CVSS 3.1 | 7.0 | High | CISA (ADP) |
Official description
do_tls_getsockopt in net/tls/tls_main.c in the Linux kernel through 6.2.6 lacks a lock_sock call, leading to a race condition (with a resultant use-after-free or NULL pointer dereference).
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: NULL Pointer Dereference
The product dereferences a pointer that it expects to be valid but is NULL.
How developers prevent this class of flaw
- For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished.
- Select a programming language that is not susceptible to these issues.
- Check the results of all functions that return a value and verify that the value is non-null before acting upon it.
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
Third-party and government advisories
- lists.debian.org/debian-lts-announce/2023/05/msg00005.htmlMailing List, Third Party Advisory
- security.netapp.com/advisory/ntap-20230427-0006/Third Party Advisory
Other vulnerabilities in Linux Kernel
- 9.8 Critical severity
- 7.0 High severity
- 7.8 High severity
- 7.1 High severity
- 7.0 High severity
- 7.8 High severity
Recent NULL Pointer Dereference vulnerabilities
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
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