CVE-2026-97934

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

tracing: Fix memory corruption from a "STACKTRACE" histogram key

"cpu", "CPU", "stacktrace" and "STACKTRACE" are generic fields, defined

with an offset and a size of zero so that the filter code can match them

by name. parse_field() maps them onto their common_* equivalents for

backward compatibility, but unlike the common_* names it hands the

placeholder back to the caller instead of NULL.

create_hist_field() takes a non-NULL field as a promise that the record

carries a stacktrace and picks HIST_FIELD_FN_STACK, so the __data_loc

word is read from offset 0, that is from common_type, and its low 16

bits are followed as an offset into the record. What is found there

becomes the length of an unbounded memcpy. Pick an event whose id is

small enough that the offset stays inside its own record and the length

is a kernel text address:

# cd /sys/kernel/tracing

# echo 'hist:keys=STACKTRACE' > events/ftrace/print/trigger

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References