CVE-2026-68136EPSS p7.2%
CVE-2026-68136CVE-2026-68136
Description
In the Linux kernel, the following vulnerability has been resolved:
net: gro: fix double aggregation of flush-marked skbs
Commit 0ab03f353d36 ("net-gro: Fix GRO flush when receiving a GSO
packet.") added a flush check to skb_gro_receive(), but
skb_gro_receive_list() lacks the same validation.
As a result, packets marked with NAPI_GRO_CB(skb)->flush may still be
re-aggregated.
This allows already-GRO'd packets with existing frag_list to be
re-aggregated into a new GRO session, corrupting the frag_list chain
structure. When skb_segment() attempts to unpack these malformed packets,
it encounters invalid state and triggers a kernel panic.
Scenario (Tethering/Device forwarding):
1. Driver: Generated aggregated packet P1 via LRO with frag_list
2. Dev A: Receives aggregated fraglist packet and flush flag set
3. Dev A: Re-enters GRO, skb_gro_receive_list() is called
4. Missing flush check allows re-aggregation despite flush flag
5. Frag_list chain becomes corrupted (loops or dan
Scoring
| EPSS | 0.18% probability of exploitation · percentile 7.2% · 2026-08-11T12:00:17Z |
| Last modified | 2026-08-10 |