SB20261015139 - Integer overflow in Linux kernel ipv4
Published: October 15, 2026
Security Bulletin ID
SB20261015139
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Information disclosure
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Integer overflow (CVE-ID: CVE-2026-98393)
CWE-ID: CWE-190 - Integer overflow
CVSSv4: 0 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to trigger a kernel warning.
The vulnerability exists due to integer overflow of the 16-bit UDP length field in the Linux kernel IPv4 packet construction code when constructing oversized UDP packets with IP_MTU_DISCOVER set to IP_PMTUDISC_PROBE. A local user can send a 65,528-byte UDP payload to trigger a kernel warning.
Exploitation requires a network device with an MTU greater than IP_MAX_MTU + 20.
Remediation
Install update from vendor's website.