Vulnerabilities

Vulnerability · CVE-2026-74633

In the Linux kernel, the following vulnerability has been resolved: tracing: Fix NULL pointer dereference in module event cache removal A module-only event filter such…

Published Aug 22, 2026 · catalog updated Oct 14, 2026 · the affected product

Check if you run it

No confirmed exploitation is on record for CVE-2026-74633. EPSS is 0.21%. Act only if a listed version of the affected product is installed.

Gaps on this record

  • No plain product name is stored. The page cannot tell you which product to check.
  • No version range is stored. A customer cannot check an installed version against this record.
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
Unknown—
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.21%
Remediation
Not established
Affected products
See sources for product scope

In the Linux kernel, the following vulnerability has been resolved: tracing: Fix NULL pointer dereference in module event cache removal A module-only event filter such as ":mod:foo" is cached with a NULL event_mod->match when foo has not been loaded. If a later write tries to remove a specific match from the same module, remove_cache_mod() passes the NULL cached match to strcmp(), causing a NULL pointer dereference. The issue can be reproduced from userspace: echo ':mod:trace_events_kunit_missing' > /sys/kernel/tracing/set_event echo '!foo_bar:mod:trace_events_kunit_missing' >> /sys/kernel/tracing/set_event The second write must be a concatenation (">>") to not include O_TRUNC as that would cause ftrace_clear_events() to clear the cached modules lines. The crash was reproduced on x86_64 QEMU while KUnit workers contended on the event tracing path: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode RIP: 0010:strcmp+0x10/0x30 Call Trace: __ftrace_set_clr_event_nolock+0x373/0x4a0 ftrace_set_clr_event+0xf0/0x180 ftrace_event_write+0xdf/0x110 vfs_write+0xf6/0x440 ksys_write+0x68/0xe0 do_syscall_64+0xf9/0x540 entry_SYSCALL_64_after_hwframe+0x77/0x7f Check event_mod->match before comparing it, consistent with the existing NULL checks for the cached system and event fields. The mismatched removal continues to return -EINVAL; a broad cached module filter is removed with "!:mod: ".

No affected version ranges are stored yet. Use the vendor advisory before you decide this record does not apply.

How to fix CVE-2026-74633

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-74633. EPSS is 0.21%. Act only if a listed version of the affected product is installed.

Which versions are affected?

Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

No weakness class is stored. EPSS 0.21%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Aug 22, 2026 · NIST NVD

    Detected

    In the Linux kernel, the following vulnerability has been resolved: tracing: Fix NULL pointer dereference in module event cache removal A module-only event filter such as ":mod:foo" is cached with a NULL event_mod->match when foo has not been loaded. If a later write tries to remove a specific match from the same module, remove_cache_mod() passes the NULL cached match to strcmp(), causing a NULL p

  2. Oct 14, 2026 · NIST NVD

    Updated

    In the Linux kernel, the following vulnerability has been resolved: tracing: Fix NULL pointer dereference in module event cache removal A module-only event filter such as ":mod:foo" is cached with a NULL event_mod->match when foo has not been loaded. If a later write tries to remove a specific match from the same module, remove_cache_mod() passes the NULL cached match to strcmp(), causing a NULL p

Sources

  • CVE.orgVulnerability recordCVE-2026-74633

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-74633

    30-day exploitation probability 0.2%

    first.org
  • NIST NVDVulnerability recordCVE-2026-74633

    In the Linux kernel, the following vulnerability has been resolved: tracing: Fix NULL pointer dereference in module event cache removal A module-only event filter such as ":mod:foo" is cached with a NULL event_mod->match when foo has not been loaded. If a later write tries to r

    nvd.nist.gov

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.