CVE Catalog

CVE-2026-64028

Low risk· EPSS 8%
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.19%

8th percentile - higher than 8% of all known CVEs

Summary

In the Linux kernel, a vulnerability in the tracing subsystem causes hist_field_name() to return NULL instead of an empty string when the field name is truncated. This leads to NULL pointer dereference in strcat() and strcmp() calls, potentially causing a system crash.

Risk Assessment

An attacker with local access can trigger a kernel panic by providing an overly long histogram variable name in a trigger string, leading to NULL pointer dereference.

Recommendation

Immediately update the Linux kernel to a version containing the fix that returns an empty string instead of NULL on field name truncation.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: tracing: Avoid NULL return from hist_field_name() on truncation hist_field_name() returns "" everywhere except the fully-qualified VAR_REF/EXPR case, where snprintf() truncation returns NULL early and bypasses the bottom NULL->"" guard. Callers don't expect NULL: strcat(expr, hist_field_name(field, 0)) at trace_events_hist.c:1758 and the strcmp() in the sort-key match loop at :4804 both deref it. system and event_name are bounded by MAX_EVENT_NAME_LEN, but the field name on a VAR_REF is kstrdup'd from a histogram variable name parsed out of the trigger string and has no length cap, so a long enough var name in a fully qualified reference can reach the truncation path. Keep the length check but leave field_name as "" on overflow.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS