Answer in brief
CVE-2026-68136 records a Unknown severity vulnerability in net: gro: fix double aggregation of flush-marked skbs. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=3a1296a38d0cf62bffb9a03c585cbd5dbf15d596 <107e1a469f53a2a70874f3f12bf6fcd23925da1d || >=3a1296a38d0cf62bffb9a03c585cbd5dbf15d596 <a4dfd46cc8f08a29c6183794790547d0945f3d45 || >=3a1296a38d0cf62bffb9a03c585cbd5dbf15d596 <fc0c0f7a207f0cd2d2aa725696c907f7d03af9e0 || >=3a1296a38d0cf62bffb9a03c585cbd5dbf15d596 <e751256486d0ded20f5a9f9863467f1dce65142f | 107e1a469f53a2a70874f3f12bf6fcd23925da1d, a4dfd46cc8f08a29c6183794790547d0945f3d45, fc0c0f7a207f0cd2d2aa725696c907f7d03af9e0, e751256486d0ded20f5a9f9863467f1dce65142f |
| Linux/Linuxgeneric | 5.6 | Not reported |
Published upstream
Aug 10, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 10, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 10, 2026
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 dangling refs) 6. Dev B: TX path calls skb_segment(), crashes on corrupted frag_list Root cause in skb_segment(): The check at line ~4891: if (hsize <= 0 && i >= nfrags && skb_headlen(list_skb) && (skb_headlen(list_skb) == len || sg)) { When frag_list is corrupted by double aggregation, when list_skb is a NULL pointer from skb->next, skb_headlen(list_skb) dereference NULL/corrupted pointers occurs. Call Trace: skb_headlen(NULL skb) skb_segment tcp_gso_segment tcp4_gso_segment inet_gso_segment skb_mac_gso_segment __skb_gso_segment skb_gso_segment validate_xmit_skb validate_xmit_skb_list sch_direct_xmit qdisc_restart __qdisc_run qdisc_run net_tx_action Fix: Add NAPI_GRO_CB(skb)->flush validation to the early-return check in skb_gro_receive_list(), matching the defensive programming pattern of skb_gro_receive().
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-68136 records a Unknown severity vulnerability in net: gro: fix double aggregation of flush-marked skbs. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=3a1296a38d0cf62bffb9a03c585cbd5dbf15d596 <107e1a469f53a2a70874f3f12bf6fcd23925da1d || >=3a1296a38d0cf62bffb9a03c585cbd5dbf15d596 <a4dfd46cc8f08a29c6183794790547d0945f3d45 || >=3a1296a38d0cf62bffb9a03c585cbd5dbf15d596 <fc0c0f7a207f0cd2d2aa725696c907f7d03af9e0 || >=3a1296a38d0cf62bffb9a03c585cbd5dbf15d596 <e751256486d0ded20f5a9f9863467f1dce65142f | 107e1a469f53a2a70874f3f12bf6fcd23925da1d, a4dfd46cc8f08a29c6183794790547d0945f3d45, fc0c0f7a207f0cd2d2aa725696c907f7d03af9e0, e751256486d0ded20f5a9f9863467f1dce65142f |
| Linux/Linuxgeneric | 5.6 | Not reported |
Published upstream
Aug 10, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 10, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 10, 2026
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 dangling refs) 6. Dev B: TX path calls skb_segment(), crashes on corrupted frag_list Root cause in skb_segment(): The check at line ~4891: if (hsize <= 0 && i >= nfrags && skb_headlen(list_skb) && (skb_headlen(list_skb) == len || sg)) { When frag_list is corrupted by double aggregation, when list_skb is a NULL pointer from skb->next, skb_headlen(list_skb) dereference NULL/corrupted pointers occurs. Call Trace: skb_headlen(NULL skb) skb_segment tcp_gso_segment tcp4_gso_segment inet_gso_segment skb_mac_gso_segment __skb_gso_segment skb_gso_segment validate_xmit_skb validate_xmit_skb_list sch_direct_xmit qdisc_restart __qdisc_run qdisc_run net_tx_action Fix: Add NAPI_GRO_CB(skb)->flush validation to the early-return check in skb_gro_receive_list(), matching the defensive programming pattern of skb_gro_receive().
Quoted source text, attributed separately from HOL analysis.