CVE-2026-97515 — i3c: master: svc: Prevent IRQ storm from false SLVSTART on NPCM845
In the Linux kernel, the following vulnerability has been resolved: i3c: master: svc: Prevent IRQ storm from false SLVSTART on NPCM845 On NPCM845, when a target on the I3C bus gets stuck holding SDA low, the controller reports a false Master Request (MR) in-band interrupt event. The driver handles this by emitting a STOP condition to restore the bus. However, the hardware quirk SVC_I3C_QUIRK_FALSE_SLVSTART indicates that emitting a STOP condition may spuriously set the SLVSTART interrupt status bit. In the Master Request case, this creates a feedback loop: the STOP triggers a new SLVSTART event, the IRQ handler fires again, the controller still reports an MR type, another STOP is emitted, and the cycle repeats indefinitely, resulting in an IRQ storm that can lock up the CPU. Clear the SLVSTART status bit explicitly after emitting the STOP in the Master Request IBI handler when the SVC_I3C_QUIRK_FALSE_SLVSTART quirk is set. This breaks the feedback loop without affecting normal SLVSTART processing, which is already guarded in the top-level IRQ handler by checking that MSTATUS is in SLVREQ state.
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)+1
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.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
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).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
≥ 0430bf9bc1ac068c8b8c540eb93e5751872efc51 and < e9b139c4684ed8593a0b779ca02ea05f460b2eec≥ 0430bf9bc1ac068c8b8c540eb93e5751872efc51 and < 1effa3adfe53cb2bb28bf5640a676b791d5ab405version 30748ce7e156f221fb91689b338a0d7df77b732aversion f2985a1de6f53abbc42c7a696ee6ba8bdecc9426version 0541822045ae043d62c941ca31fa76871e436b5eversion 1ea4653cff35c29d1dd0b14ad9c8245e7318f337version d231fb443d8d4042f0dd705b93beba8c916a7344≥ 5.15.185 and < 5.16 and 5 more≥ 6.1.141 and < 6.2≥ 6.6.93 and < 6.7≥ 6.12.31 and < 6.13≥ 6.14.9 and < 6.15version 6.15 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
EPSS over time FIRST
Oct 15, 2026 → Oct 16, 2026 · 2 reading(s) · max 0.15%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Not enough vector or weakness data: use the affected application’s logs as a starting point.
Timeline
What happened to this CVE, newest first.
- 2026
- Record published
- Affected products added · linux/linux
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
2 on the record
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 1d
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 1d
- Unknown CVE-2026-98430 RDMA/efa: Keep admin queues alive while IRQ is registered 2d
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 2d
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 2d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 2d
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 CVSS score published by NVD, the CNA, CISA or GitHub so far.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- 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-2026-97515 is "i3c: master: svc: Prevent IRQ storm from false SLVSTART on NPCM845", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.15% 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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