CVE-2026-98078: ipvs: fix reversed sequence option serialization
In the Linux kernel, the following vulnerability has been resolved:
ipvs: fix reversed sequence option serialization
htonseq() expects the host-order source first and the unaligned network-order destination second. The version 1 sync sender passes these arguments in reverse for both sequence blocks. This leaves 24 bytes of the kmalloc-backed message unwritten. It may disclose stale heap data and replace the live connection sequence state with values read from the buffer.
Pass the connection sequence state as the source and the message payload as the destination for both blocks.
Affected Software
Event History
Frequently Asked Questions
Which systems are exposed to this issue?
Systems using the Linux kernel IPVS version 1 synchronization sender are affected. The issue occurs in the handling of both sequence blocks in sync messages.
What is the practical impact of the flawed serialization?
The sync message can retain 24 bytes of unwritten kmalloc-backed memory, potentially disclosing stale heap data. It can also overwrite live connection sequence state with values read from that buffer.