Kernel crash via unchecked negative ifindex
Published Dec 9, 2025 · Updated May 11, 2026
Improper input validation in Linux kernel Open vSwitch allows local users to trigger a kernel crash through a crafted negative ifindex. The datapath and vport Netlink policies decode ifindex attributes as unsigned values, allowing large inputs to become negative signed interface indexes instead of enforcing a zero minimum. Reachability requires access to OVS datapath or vport configuration, and the demonstrated consequence is a kernel paging failure and service interruption.
Summary
What happened
Improper input validation in Linux kernel Open vSwitch allows local users to trigger a kernel crash through a crafted negative ifindex. The datapath and vport Netlink policies decode ifindex attributes as unsigned values, allowing large inputs to become negative signed interface indexes instead of enforcing a zero minimum. Reachability requires access to OVS datapath or vport configuration, and the demonstrated consequence is a kernel paging failure and service interruption.
The record
- CVE
- CVE-2023-53843
- Published
- Dec 9, 2025
- Updated
- May 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1499.004
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Dec 9, 2025CVE publishedPublication date reported by the CVE source.
- May 11, 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=54c4ef34c4b6f9720fded620e2893894f9f2c554 <881faff9e548a7ddfb11595be7c1c649217d27db
- Affected versionversion=54c4ef34c4b6f9720fded620e2893894f9f2c554 <a552bfa16bab4ce901ee721346a28c4e483f4066
- Affected versionversion=54c4ef34c4b6f9720fded620e2893894f9f2c554 <c965a58376146dcfdda186819462e8eb3aadef3a
- Affected versionversion=6.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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.
Weakness, pattern, technique
Public exploit references
- syzbot ovs_vport_add reproducerproof of concept · demonstrated
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