CVE-2026-98403
s390/boot: Avoid IPL parameter append past command line
Description
In the Linux kernel, the following vulnerability has been resolved: s390/boot: Avoid IPL parameter append past command line A command line may occupy all but the terminating byte of COMMAND_LINE_SIZE. In that case append_ipl_block_parm() passes a zero size to the IPL parameter conversion helpers and points the destination one byte past early_command_line. The helpers subtract one from the unsigned size and write the converted parameter outside the command line buffer. Convert the IPL parameter in the command line parsing buffer first. A parameter beginning with '=' can then replace the existing command line regardless of its length, while other parameters are appended only when space remains.
INFO
Published Date :
Oct. 14, 2026, 2:17 p.m.
Last Modified :
Oct. 14, 2026, 2:17 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Update the Linux kernel to the latest version.
- Apply the specific patch for s390/boot vulnerability.
- Review and recompile kernel if necessary.
- Test system stability after update.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-98403.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-98403 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-98403
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-98403 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-98403 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Oct. 14, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: s390/boot: Avoid IPL parameter append past command line A command line may occupy all but the terminating byte of COMMAND_LINE_SIZE. In that case append_ipl_block_parm() passes a zero size to the IPL parameter conversion helpers and points the destination one byte past early_command_line. The helpers subtract one from the unsigned size and write the converted parameter outside the command line buffer. Convert the IPL parameter in the command line parsing buffer first. A parameter beginning with '=' can then replace the existing command line regardless of its length, while other parameters are appended only when space remains. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/98xxx/CVE-2026-98403.json">CVE-2026-98403</a> Added Reference https://git.kernel.org/stable/c/73eec5a0d55916d7e1115f5d03a7ffc06d6215cf Added Reference https://git.kernel.org/stable/c/8d11bfec8666f8409fac9072e9c25b691d3e30ac Added Reference https://git.kernel.org/stable/c/af9866021a00ab9eeacf0c33ee73f3d134b4ed70 Added Reference https://git.kernel.org/stable/c/d76181dfabdaa720703167393704efacba343442