Kernel memory corruption via undersized qeth ioctl buffer
Published Aug 26, 2026 · Updated Aug 26, 2026
Out-of-bounds write in Linux s390 qeth allows local users to corrupt kernel memory via a crafted SNMP or ARP query ioctl. qeth_snmp_command() and qeth_l3_arp_query() accept udata_len below fixed offsets, so unsigned subtraction wraps and permits memcpy() beyond the allocation. The path requires an unprivileged local user on an IBM Z or LinuxONE LPAR with a qeth interface; corruption supports privilege escalation and kernel crash.
Summary
What happened
Out-of-bounds write in Linux s390 qeth allows local users to corrupt kernel memory via a crafted SNMP or ARP query ioctl. qeth_snmp_command() and qeth_l3_arp_query() accept udata_len below fixed offsets, so unsigned subtraction wraps and permits memcpy() beyond the allocation. The path requires an unprivileged local user on an IBM Z or LinuxONE LPAR with a qeth interface; corruption supports privilege escalation and kernel crash.
The record
- CVE
- CVE-2026-80584
- Published
- Aug 26, 2026
- Updated
- Aug 26, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-787, T1068
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 26, 2026CVE publishedPublication date reported by the CVE source.
- Aug 26, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2.6.26
- Affected versionversion=4a71df50047f0db65ea09b1be155852e81a45eba <3083818e67bcd656965797fbac9a3d6c1d44f78a
- Affected versionversion=4a71df50047f0db65ea09b1be155852e81a45eba <46443eaddebd84c51940857b11787229be169dec
- Affected versionversion=4a71df50047f0db65ea09b1be155852e81a45eba <75fb3151513d7d9f77a8f9545418279b119c06b8
- Affected versionversion=4a71df50047f0db65ea09b1be155852e81a45eba <91935843f9396a9e45253e2c0d4337ca1371754b
- Affected versionversion=4a71df50047f0db65ea09b1be155852e81a45eba <9d00eeb2d27f4cc817c5e408760226d43f811ec6
- Affected versionversion=4a71df50047f0db65ea09b1be155852e81a45eba <a3083647747942ea32faf14560d6397ff3068046
- Affected versionversion=4a71df50047f0db65ea09b1be155852e81a45eba <cc423f4105fe145b33e1d7cad34245a798358f73
- Affected versionversion=4a71df50047f0db65ea09b1be155852e81a45eba <d141f087b1af656f055d7c5793a3e87817ba0bbe
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo