CVE-2026-53300 — net: enetc: fix NTMP DMA use-after-free issue
In the Linux kernel, the following vulnerability has been resolved: net: enetc: fix NTMP DMA use-after-free issue The AI-generated review reported a potential DMA use-after-free issue [1]. If netc_xmit_ntmp_cmd() times out and returns an error, the pending command is not explicitly aborted, while ntmp_free_data_mem() unconditionally frees the DMA buffer. If the buffer has already been reallocated elsewhere, this may lead to silent memory corruption. Because the hardware eventually processes the pending command and perform a DMA write of the response to the physical address of the freed buffer. To resolve this issue, this patch does the following modifications: 1. Convert cbdr->ring_lock from a spinlock to a mutex The lock was originally a spinlock in case NTMP operations might be invoked from atomic context. After downstream support for all NTMP tables, no such usage has materialized. A mutex lock is now required because the driver now needs to reclaim used BDs and release associated DMA memory within the lock's context, while dma_free_coherent() might sleep. 2. Introduce software command BD (struct netc_swcbd) The hardware write-back overwrites the addr and len fields of the BD, so the driver cannot rely on the hardware BD to free the associated DMA memory. The driver now maintains a software shadow BD storing the DMA buffer pointer, DMA address, and size. And netc_xmit_ntmp_cmd() only reclaims older BDs when the number of used BDs reaches NETC_CBDR_CLEAN_WORK (16). The software BD enables correct DMA memory release. With this, struct ntmp_dma_buf and ntmp_free_data_mem() are no longer needed and are removed. 3. Require callers to hold ring_lock across netc_xmit_ntmp_cmd() netc_xmit_ntmp_cmd() releases the ring_lock before the caller finishes consuming the response. At this point, if a concurrent thread submits a new command, it may trigger ntmp_clean_cbdr() and free the DMA buffer while it is still in use. Move ring_lock ownership to the caller to ensure the response buffer cannot be reclaimed prematurely. So the helpers ntmp_select_and_lock_cbdr() and ntmp_unlock_cbdr() are added. These changes eliminate the DMA use-after-free condition and ensure safe and consistent BD reclamation and DMA buffer lifecycle management.
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 0.2% (30-day exploitation probability)+1
- 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.
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)
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 | ≥ 4701073c3debd16d7f534f3eb808bd9b50601c0c and < 37c8933064be714ee672b0a0523c2fd045b73b3d≥ 4701073c3debd16d7f534f3eb808bd9b50601c0c and < 655d9ce9b1d3db0aa5271acb5e5101c66bd0d58b≥ 4701073c3debd16d7f534f3eb808bd9b50601c0c and < 3cade698881eb238f88cbbfec82acc2110440a3fversion 6.16 | Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel | ≥ 6.16 and < 6.18.33≥ 6.19 and < 7.0.10 | 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 |
|---|---|---|---|---|---|
| 7.8 | CVSS 3.1 | High | 1.8 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 7.8 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: 416baaa9-dc9f-4396-8d5f-8c081fb06d67) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
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 · 7.8
- Source status changed · → Analyzed
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
3 on the record
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 10h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 10h
- Unknown CVE-2026-98430 RDMA/efa: Keep admin queues alive while IRQ is registered 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-2026-53300 is "net: enetc: fix NTMP DMA use-after-free issue", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.8 describes technical severity. EPSS 0.17% 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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