Linux: NULL Pointer Dereference
CVE-2026-68157 is a high-severity NULL pointer dereference vulnerability in Linux, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions cbfcba275326c8c7dae9acd8f4a0d4c316fdafb0, 8ff579ac03d6e9d17d6d9c8443110167c14a382d, 6a4b75d90f0cfbf22c14742ab35a803bc13f36ec 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 0.7% chance of exploitation within 30 days, higher than 54% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to cbfcba275326c8c7dae9acd8f4a0d4c316fdafb0 or 8ff579ac03d6e9d17d6d9c8443110167c14a382d or 6a4b75d90f0cfbf22c14742ab35a803bc13f36ec or c46d82c47afc968d6ee8ef4470fa2dd35b765c21, whichever matches your release line, or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 117d96a04f007ce8fc2e292369056c3bd09f6f63 up to, but not including, cbfcba275326c8c7dae9acd8f4a0d4c316fdafb0; 117d96a04f007ce8fc2e292369056c3bd09f6f63 up to, but not including, 8ff579ac03d6e9d17d6d9c8443110167c14a382d; 117d96a04f007ce8fc2e292369056c3bd09f6f63 up to, but not including, 6a4b75d90f0cfbf22c14742ab35a803bc13f36ec; 117d96a04f007ce8fc2e292369056c3bd09f6f63 up to, but not including, c46d82c47afc968d6ee8ef4470fa2dd35b765c21; 117d96a04f007ce8fc2e292369056c3bd09f6f63 up to, but not including, 3767c9f0c1bbd98dd25cb088356a0fc6c1f09f50; 117d96a04f007ce8fc2e292369056c3bd09f6f63 up to, but not including, 4716a64b7cc2797741f7be4e283ace78a9dff37d; 117d96a04f007ce8fc2e292369056c3bd09f6f63 up to, but not including, db9cc9fd9660b2d69ee66f5a4cbec83c21a1c64d; 117d96a04f007ce8fc2e292369056c3bd09f6f63 up to, but not including, bbeae12fda3384a90fbebc8a19ba9d33f85b5361; and 1 more ranges | cbfcba275326c8c7dae9acd8f4a0d4c316fdafb0, 8ff579ac03d6e9d17d6d9c8443110167c14a382d, 6a4b75d90f0cfbf22c14742ab35a803bc13f36ec, c46d82c47afc968d6ee8ef4470fa2dd35b765c21, 3767c9f0c1bbd98dd25cb088356a0fc6c1f09f50, 4716a64b7cc2797741f7be4e283ace78a9dff37d |
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
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA.
Official description
In the Linux kernel, the following vulnerability has been resolved: libceph: guard missing CRUSH type name lookup Localized read selection can walk a parent bucket whose name exists in the CRUSH map while its type has no matching entry in type_names. get_immediate_parent() then dereferences a NULL type_cn and passes an invalid pointer into strcmp(), causing a null-ptr-deref. Skip such malformed parent buckets unless both the bucket name and type name metadata are present. This keeps malformed hierarchy data from crashing locality lookup and safely falls back to "not local". [ idryomov: add WARN_ON_ONCE ]
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: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other references
- git.kernel.org/stable/c/3767c9f0c1bbd98dd25cb088356a0fc6c1f09f50
- git.kernel.org/stable/c/4716a64b7cc2797741f7be4e283ace78a9dff37d
- git.kernel.org/stable/c/6a4b75d90f0cfbf22c14742ab35a803bc13f36ec
- git.kernel.org/stable/c/8ff579ac03d6e9d17d6d9c8443110167c14a382d
- git.kernel.org/stable/c/bbeae12fda3384a90fbebc8a19ba9d33f85b5361
- git.kernel.org/stable/c/c46d82c47afc968d6ee8ef4470fa2dd35b765c21
- git.kernel.org/stable/c/cbfcba275326c8c7dae9acd8f4a0d4c316fdafb0
- git.kernel.org/stable/c/db9cc9fd9660b2d69ee66f5a4cbec83c21a1c64d
Recent NULL Pointer Dereference vulnerabilities
- 7.5 High severity
- 9.8 Critical severity
- 8.8 High severity
- 7.8 High severity
- 7.5 High severity
- 9.8 Critical severity
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