Answer in brief
CVE-2026-68296 records a Unknown severity vulnerability in net: gre: fix lltx regression for GRE tunnels with SEQ/CSUM. 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 | >=00d066a4d4edbe559ba6c35153da71d4b2b8a383 <9f948e9aede9678f4103457daf2bc9dd54c65a06 || >=00d066a4d4edbe559ba6c35153da71d4b2b8a383 <15a1c5f2ed2eeb3daad8d5766fd506aeda4710f3 || >=00d066a4d4edbe559ba6c35153da71d4b2b8a383 <2bffe379023512d280337c70faeb6a8cc435db5e || >=00d066a4d4edbe559ba6c35153da71d4b2b8a383 <675ed582c1aa4d919dd535490de08c015005c653 | 9f948e9aede9678f4103457daf2bc9dd54c65a06, 15a1c5f2ed2eeb3daad8d5766fd506aeda4710f3, 2bffe379023512d280337c70faeb6a8cc435db5e, 675ed582c1aa4d919dd535490de08c015005c653 |
| Linux/Linuxgeneric | 6.12 | 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: gre: fix lltx regression for GRE tunnels with SEQ/CSUM Before commit 00d066a4d4ed ("netdev_features: convert NETIF_F_LLTX to dev->lltx"), NETIF_F_LLTX was set unconditionally in both __gre_tunnel_init() and ip6gre_tnl_init_features() alongside GRE_FEATURES: dev->features |= GRE_FEATURES | NETIF_F_LLTX; When that commit converted NETIF_F_LLTX to the dev->lltx flag, it placed 'dev->lltx = true' after the SEQ/CSUM early returns instead of before them. This causes GRE/GRETAP/ip6gre tunnels with SEQ or CSUM+encap to lose lockless TX, reintroducing _xmit_lock acquisition around their ndo_start_xmit. Since GRE xmit re-enters the stack via ip_tunnel_xmit(), holding _xmit_lock risks ABBA deadlock with the underlay device. CPU0 CPU1 ---- ---- lock(&qdisc_xmit_lock_key#6); lock(&qdisc_xmit_lock_key#3); lock(&qdisc_xmit_lock_key#6); lock(&qdisc_xmit_lock_key#3); Fix by moving dev->lltx = true before the early returns in both functions, restoring the original unconditional behavior.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-68296 records a Unknown severity vulnerability in net: gre: fix lltx regression for GRE tunnels with SEQ/CSUM. 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 | >=00d066a4d4edbe559ba6c35153da71d4b2b8a383 <9f948e9aede9678f4103457daf2bc9dd54c65a06 || >=00d066a4d4edbe559ba6c35153da71d4b2b8a383 <15a1c5f2ed2eeb3daad8d5766fd506aeda4710f3 || >=00d066a4d4edbe559ba6c35153da71d4b2b8a383 <2bffe379023512d280337c70faeb6a8cc435db5e || >=00d066a4d4edbe559ba6c35153da71d4b2b8a383 <675ed582c1aa4d919dd535490de08c015005c653 | 9f948e9aede9678f4103457daf2bc9dd54c65a06, 15a1c5f2ed2eeb3daad8d5766fd506aeda4710f3, 2bffe379023512d280337c70faeb6a8cc435db5e, 675ed582c1aa4d919dd535490de08c015005c653 |
| Linux/Linuxgeneric | 6.12 | 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: gre: fix lltx regression for GRE tunnels with SEQ/CSUM Before commit 00d066a4d4ed ("netdev_features: convert NETIF_F_LLTX to dev->lltx"), NETIF_F_LLTX was set unconditionally in both __gre_tunnel_init() and ip6gre_tnl_init_features() alongside GRE_FEATURES: dev->features |= GRE_FEATURES | NETIF_F_LLTX; When that commit converted NETIF_F_LLTX to the dev->lltx flag, it placed 'dev->lltx = true' after the SEQ/CSUM early returns instead of before them. This causes GRE/GRETAP/ip6gre tunnels with SEQ or CSUM+encap to lose lockless TX, reintroducing _xmit_lock acquisition around their ndo_start_xmit. Since GRE xmit re-enters the stack via ip_tunnel_xmit(), holding _xmit_lock risks ABBA deadlock with the underlay device. CPU0 CPU1 ---- ---- lock(&qdisc_xmit_lock_key#6); lock(&qdisc_xmit_lock_key#3); lock(&qdisc_xmit_lock_key#6); lock(&qdisc_xmit_lock_key#3); Fix by moving dev->lltx = true before the early returns in both functions, restoring the original unconditional behavior.
Quoted source text, attributed separately from HOL analysis.