CVE-2026-98403: Linux kernel · s390/boot: Avoid IPL parameter append past command line
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in d76181dfabdaa720703167393704efacba343442 : patch Linux kernel soon.
Data as of 26 Oct 2026, 12:55 UTC
Rated High 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 d76181dfabdaa720703167393704efacba343442, af9866021a00ab9eeacf0c33ee73f3d134b4ed70, 73eec5a0d55916d7e1115f5d03a7ffc06d6215cf +1
Exploitation evidence
Disclosed: evidence found.
CVE published 14 Oct 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.
What to do
Upgrade Linux kernel to d76181dfabdaa720703167393704efacba343442, af9866021a00ab9eeacf0c33ee73f3d134b4ed70, 73eec5a0d55916d7e1115f5d03a7ffc06d6215cf or 8d11bfec8666f8409fac9072e9c25b691d3e30ac.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A patch is available and has been applied in specific Linux kernel commits. Systems running the affected version 5.16 should update to a fixed kernel version containing these commits. Since this is a kernel-level vulnerability, applying the official kernel update is the recommended remediation.
Description
A vulnerability in the Linux kernel's s390 boot code could cause a buffer overflow when appending IPL parameters to the command line if the command line occupies all but the terminating byte of the buffer. This flaw has been fixed by changing how IPL parameters are appended or replaced in the command line buffer.
References
- git.kernel.org/stable/c/af9866021a00ab9eeacf0c33ee73f3d134b4ed70 (opens in a new tab)
- git.kernel.org/stable/c/73eec5a0d55916d7e1115f5d03a7ffc06d6215cf (opens in a new tab)
- git.kernel.org/stable/c/8d11bfec8666f8409fac9072e9c25b691d3e30ac (opens in a new tab)
- git.kernel.org/stable/c/d76181dfabdaa720703167393704efacba343442 (opens in a new tab)