CVE-2026-72423

In the Linux kernel, the following vulnerability has been resolved: bpf: Guard conntrack opts error writes The conntrack lookup and allocation kfuncs take an opts pointer together with an opts__sz argument. The verifier checks only the memory range described by opts__sz, but the wrappers unconditionally write opts->error whenever the internal lookup or allocation helper returns an error. For an invalid size smaller than the end of opts->error, that write can land outside the verifier-checked range. Keep returning NULL for invalid arguments, but only report the error through opts->error when the supplied size includes the field. This preserves error reporting for the supported 12-byte and 16-byte layouts, and for other invalid sizes that still include opts->error.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.0 / Impact : 6.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://git.kernel.org/stable/c/6f6183a39533d727deaa5061cadae6dd9e6744d0
https://git.kernel.org/stable/c/dd74c80203842a21b2ebb9f70d1260d9aa20fa05

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-15 06:22

Updated : 2026-08-17 06:19

NVD link : CVE-2026-72423

Mitre link : CVE-2026-72423

CVE.ORG link : CVE-2026-72423

JSON object : View

Products Affected

No product.

CWE

No CWE.

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