CVE-2026-74695 (GCVE-0-2026-74695)
Vulnerability from cvelistv5
Published
2026-08-22 15:32
Modified
2026-10-21 12:46
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
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
Impacted products
Vendor Product Version
Linux Linux Version: 2a79fd3908acd88e6cb0e620c314d7b1fee56a02
Version: 2a79fd3908acd88e6cb0e620c314d7b1fee56a02
Version: 2a79fd3908acd88e6cb0e620c314d7b1fee56a02
Version: 2a79fd3908acd88e6cb0e620c314d7b1fee56a02
Version: 2a79fd3908acd88e6cb0e620c314d7b1fee56a02
Version: b4b1adf2e66ecc7125c4117e7aad9ff61e2cfd27
Version: 209dedf806d31095968f54323dbe62525b077b33
Version: 4.16.15   ≤
Version: 4.17.1   ≤
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