CVE-2026-46021 — thermal: core: Fix thermal zone governor cleanup issues
In the Linux kernel, the following vulnerability has been resolved: thermal: core: Fix thermal zone governor cleanup issues If thermal_zone_device_register_with_trips() fails after adding a thermal governor to the thermal zone being registered, the governor is not removed from it as appropriate which may lead to a memory leak. In turn, thermal_zone_device_unregister() calls thermal_set_governor() without acquiring the thermal zone lock beforehand which may race with a governor update via sysfs and may lead to a use-after-free in that case. Address these issues by adding two thermal_set_governor() calls, one to thermal_release() to remove the governor from the given thermal zone, and one to the thermal zone registration error path to cover failures preceding the thermal zone device registration.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.1% (30-day exploitation probability)+0
- Technical severity (medium)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux, Linux Linux Kernel).
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
≥ e33df1d2f3a0141cd79e770f31999ba0dd7ebfa8 and < a172fa18bc370b776ac1510abb0dcb50a7a35fac≥ e33df1d2f3a0141cd79e770f31999ba0dd7ebfa8 and < 8e563d8db50f303171aceb79eec0807e7ba06951≥ e33df1d2f3a0141cd79e770f31999ba0dd7ebfa8 and < d4eb861adde5ce22e459fbd29366f47bb2167977≥ e33df1d2f3a0141cd79e770f31999ba0dd7ebfa8 and < 37a430a2d4e66ec8238da6c7f7e48809bf265e13≥ e33df1d2f3a0141cd79e770f31999ba0dd7ebfa8 and < f412e541d25a3dfaf3d53e012ade6ff03cae8a45≥ e33df1d2f3a0141cd79e770f31999ba0dd7ebfa8 and < 75f8f3c3e09122270986de9d7aa347d701676761≥ e33df1d2f3a0141cd79e770f31999ba0dd7ebfa8 and < 64d4ebf91d082034bbc5ae3ba2d7fd800bc02d06≥ e33df1d2f3a0141cd79e770f31999ba0dd7ebfa8 and < 41ff66baf81c6541f4f985dd7eac4494d03d9440 and 1 moreversion 4.2 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel | ≥ 4.2 and < 6.6.140≥ 6.7 and < 6.12.86≥ 6.13 and < 6.18.27≥ 6.19 and < 7.0.4 | Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 5.5 | CVSS 3.1 | Medium | 1.8 | 3.6 | nvd@nist.gov via NIST National Vulnerability Database |
| 5.5 | CVSS 3.1 | Medium | — | — | GitHub, Inc. via GitHub Security Advisories |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
CWE-401 · Missing Release of Memory after Effective Lifetime
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.17%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- Fix documented
- CVSS changed · 5.5
- Source status changed · → Modified
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 14, 2026 – Oct 14, 2026
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
13 on the record
- git.kernel.org/stable/c/37a430a2d4e66ec8238da6c7f7e48809bf265e13
- git.kernel.org/stable/c/f412e541d25a3dfaf3d53e012ade6ff03cae8a45
- git.kernel.org/stable/c/64d4ebf91d082034bbc5ae3ba2d7fd800bc02d06
- git.kernel.org/stable/c/41ff66baf81c6541f4f985dd7eac4494d03d9440
- git.kernel.org/stable/c/75f8f3c3e09122270986de9d7aa347d701676761
- git.kernel.org/stable/c/d4eb861adde5ce22e459fbd29366f47bb2167977
- git.kernel.org/stable/c/8e563d8db50f303171aceb79eec0807e7ba06951
- cert-portal.siemens.com/productcert/html/ssa-457936.html
- cert-portal.siemens.com/productcert/html/ssa-019113.html
- cert-portal.siemens.com/productcert/html/ssa-784472.html
- github.com/advisories/GHSA-7x76-cw6q-rm95
- git.kernel.org/stable/c/a172fa18bc370b776ac1510abb0dcb50a7a35fac
- nvd.nist.gov/vuln/detail/CVE-2026-46021
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 13h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 13h
- Unknown CVE-2026-98431 RDMA/uverbs: Fix mmap_lock/disassociation_lock circular dependency 1d
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CISA SSVC assessment.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-46021 is "thermal: core: Fix thermal zone governor cleanup issues", rated Medium. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.5 describes technical severity. EPSS 0.14% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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