In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_flow_table:...
🔗 CVE IDs covered (1)
📋 Description
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_flow_table: drop existing skb dst before skb_dst_set_noref()
Incoming skbs passing through netfilter flowtable offload hooks (or XFRM offload path) might already carry a ref-counted dst_entry assigned during earlier RX or routing steps.
Calling skb_dst_set_noref() when skb already holds a ref-counted dst overwrites skb->_skb_refdst, leaking the previous dst_entry reference count and triggering a DEBUG_NET_WARN_ON_ONCE assertion in skb_dst_check_unset():
WARNING: at skb_dst_check_unset include/linux/skbuff.h:1170 WARNING: at skb_dst_set_noref include/linux/skbuff.h:1234 WARNING: at nf_flow_offload_ip_hook+0xf6c/0x2b60 net/netfilter/nf_flow_table_ip.c:864
Drop any existing dst_entry reference with skb_dst_drop(skb) before setting the non-referenced flowtable destination.
🔗 References (5)
- https://nvd.nist.gov/vuln/detail/CVE-2026-74695
- https://git.kernel.org/stable/c/12afa450a6a6c0cce2c42b7545a9958f62d8a00c
- https://git.kernel.org/stable/c/538e67e8c7889cf5f93951f5309d1bcb41f86036
- https://git.kernel.org/stable/c/8aecf0bbcc72605592134c917c222207d8f63ab0
- https://github.com/advisories/GHSA-cx4h-xjm7-pqxp