VulnerabilityPublished 25 Sep 2026Updated 19 Oct 2026

CVE-2026-98086: Linux kernel · ALSA: ump: do not touch legacy_rmidi before it exists

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in d6f9af093dc91dac8848a01e417b8109c651c0b2 : update Linux kernel when convenient.

Data as of 26 Oct 2026, 14:05 UTC

Severity

Medium

Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD

EPSS: 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in d6f9af093dc91dac8848a01e417b8109c651c0b2, adeee7187694719890aaffdc14b7e89cfd736f1d, a4cef20cd473e0640fefd38094d4baac0ec76ae3 +2

Exploitation evidence

Disclosed: evidence found.
CVE published 25 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 37e0e14128e0685267dc5c037bf655421a6ce2ea, < d6f9af093dc91dac8848a01e417b8109c651c0b2	Fixed in d6f9af093dc91dac8848a01e417b8109c651c0b2
LinuxLinux	Affected ≥ 37e0e14128e0685267dc5c037bf655421a6ce2ea, < adeee7187694719890aaffdc14b7e89cfd736f1d	Fixed in adeee7187694719890aaffdc14b7e89cfd736f1d
LinuxLinux	Affected ≥ 37e0e14128e0685267dc5c037bf655421a6ce2ea, < a4cef20cd473e0640fefd38094d4baac0ec76ae3	Fixed in a4cef20cd473e0640fefd38094d4baac0ec76ae3
LinuxLinux	Affected ≥ 37e0e14128e0685267dc5c037bf655421a6ce2ea, < 228075f31b141395233218712242913125ace4e0	Fixed in 228075f31b141395233218712242913125ace4e0
LinuxLinux	Affected ≥ 37e0e14128e0685267dc5c037bf655421a6ce2ea, < 1c8e01792adf91879322f1ad752f1814de8b7e7d	Fixed in 1c8e01792adf91879322f1ad752f1814de8b7e7d
LinuxLinux	Affected =6.5	Fixed in–

AI-suggested

A fix is available in the Linux kernel as indicated by the fixed commit versions. Users and administrators should update to a Linux kernel version that includes these fixes to resolve the issue.

Description

A vulnerability in the Linux kernel ALSA ump component involves improper handling of the legacy_rmidi pointer before it is initialized. This can lead to a null pointer dereference when a UMP packet arrives during a specific timing window, causing a kernel memory safety issue. The flaw was fixed by adding proper guards to ensure legacy_rmidi is accessed only after it exists.

Impact

This vulnerability can cause a kernel null pointer dereference, leading to a denial of service via kernel crash. There is no indication of privilege escalation or code execution. No known exploits in the wild have been reported.

Summary

The Linux kernel ALSA ump component had a vulnerability where snd_ump_parse_endpoint() set a parsed flag indicating endpoint info was parsed, but this flag was incorrectly used to assume the legacy rawmidi device (legacy_rmidi) was initialized. If a UMP packet arrived before legacy_rmidi was set, ump_handle_ep_name_msg() would call ump_legacy_set_rawmidi_name(), which uses snprintf() on a NULL legacy_rmidi pointer, causing a kernel null pointer dereference detected by KASAN. The fix involved guarding access to legacy_rmidi so it is only touched after it is confirmed to exist.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 12:51 UTC

Technical details

References

Community reviews

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