CVE-2025-38004 — can: bcm: add locking for bcm_op runtime updates
In the Linux kernel, the following vulnerability has been resolved: can: bcm: add locking for bcm_op runtime updates The CAN broadcast manager (CAN BCM) can send a sequence of CAN frames via hrtimer. The content and also the length of the sequence can be changed resp reduced at runtime where the 'currframe' counter is then set to zero. Although this appeared to be a safe operation the updates of 'currframe' can be triggered from user space and hrtimer context in bcm_can_tx(). Anderson Nascimento created a proof of concept that triggered a KASAN slab-out-of-bounds read access which can be prevented with a spin_lock_bh. At the rework of bcm_can_tx() the 'count' variable has been moved into the protected section as this variable can be modified from both contexts too.
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 0.3% (30-day exploitation probability)+3
- Technical severity (high)+6
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.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
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)
- 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 (Debian Debian Linux, 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 |
|---|---|---|---|---|
| Debian | Debian Linux | version 11.0 | Vulnerable | NIST National Vulnerability Database |
| Linux | Linux |
version 2.6.25≥ ffd980f976e7fd666c2e61bf8ab35107efd11828 and < c2aba69d0c36a496ab4f2e81e9c2b271f2693fd7≥ ffd980f976e7fd666c2e61bf8ab35107efd11828 and < c4e8a172501e677ebd8ea9d9161d97dc4df56fbd≥ ffd980f976e7fd666c2e61bf8ab35107efd11828 and < cc55dd28c20a6611e30596019b3b2f636819a4c0≥ ffd980f976e7fd666c2e61bf8ab35107efd11828 and < 76c84c3728178b2d38d5604e399dfe8b0752645e≥ ffd980f976e7fd666c2e61bf8ab35107efd11828 and < 2a437b86ac5a9893c902f30ef66815bf13587bf6≥ ffd980f976e7fd666c2e61bf8ab35107efd11828 and < fbd8fdc2b218e979cfe422b139b8f74c12419d1f≥ ffd980f976e7fd666c2e61bf8ab35107efd11828 and < 7595de7bc56e0e52b74e56c90f7e247bf626d628 and 1 more≥ ffd980f976e7fd666c2e61bf8ab35107efd11828 and < 8f1c022541bf5a923c8d6fa483112c15250f30a4 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel |
version 6.15-rc5version 6.15-rc7version 6.15-rc6version 6.15-rc4version 6.15-rc3version 6.15-rc2version 6.15-rc1≥ 6.13 and < 6.14.9 and 6 more≥ 6.7 and < 6.12.31≥ 6.2 and < 6.6.93≥ 5.16 and < 6.1.141≥ 5.11 and < 5.15.185≥ 5.5 and < 5.10.238≥ 2.6.25 and < 5.4.294 |
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 |
|---|---|---|---|---|---|
| 7.3 | CVSS 3.1 | High | 1.8 | 5.5 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 7.3 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
| 7.1 | CVSS 3.1 | High | 1.8 | 5.2 | nvd@nist.gov via NIST National Vulnerability Database |
| 7.1 | CVSS 3.1 | High | — | — | GitHub, Inc. via GitHub Security Advisories |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
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
- SSVC assessment updated
- Record published
- Fix documented
- Affected products added · linux/linux kernel, debian/debian linux
- CVSS changed · 7.1
- Source status changed · → Modified
- Record created in this database
- 2025
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 15, 2026 – Oct 15, 2026
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
12 on the record
- git.kernel.org/stable/c/7595de7bc56e0e52b74e56c90f7e247bf626d628
- git.kernel.org/stable/c/fbd8fdc2b218e979cfe422b139b8f74c12419d1f
- git.kernel.org/stable/c/c2aba69d0c36a496ab4f2e81e9c2b271f2693fd7
- git.kernel.org/stable/c/76c84c3728178b2d38d5604e399dfe8b0752645e
- git.kernel.org/stable/c/c4e8a172501e677ebd8ea9d9161d97dc4df56fbd
- git.kernel.org/stable/c/cc55dd28c20a6611e30596019b3b2f636819a4c0
- git.kernel.org/stable/c/2a437b86ac5a9893c902f30ef66815bf13587bf6
- git.kernel.org/stable/c/8f1c022541bf5a923c8d6fa483112c15250f30a4
- lists.debian.org/debian-lts-announce/2025/10/msg00007.html
- nvd.nist.gov/vuln/detail/CVE-2025-38004
- github.com/advisories/GHSA-29qg-42xm-553c
- lists.debian.org/debian-lts-announce/2025/10/msg00008.html
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 12h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 12h
- Unknown CVE-2026-98431 RDMA/uverbs: Fix mmap_lock/disassociation_lock circular dependency 1d
- Unknown CVE-2026-98430 RDMA/efa: Keep admin queues alive while IRQ is registered 1d
- Unknown CVE-2026-98429 RDMA/efa: Keep EQ resources alive while IRQ is registered 1d
- Unknown CVE-2026-98428 ALSA: usb: 6fire: Avoid embedded URBs 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 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-2025-38004 is "can: bcm: add locking for bcm_op runtime updates", rated High. It affects Debian Linux (Debian); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.1 describes technical severity. EPSS 0.26% 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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