CVE-2026-31406 (GCVE-0-2026-31406)
Vulnerability from cvelistv5 – Published: 2026-04-06 07:38 – Updated: 2026-08-05 12:22
VLAI
EPSS
VEX
Title
xfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini()
Summary
In the Linux kernel, the following vulnerability has been resolved:
xfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini()
After cancel_delayed_work_sync() is called from
xfrm_nat_keepalive_net_fini(), xfrm_state_fini() flushes remaining
states via __xfrm_state_delete(), which calls
xfrm_nat_keepalive_state_updated() to re-schedule nat_keepalive_work.
The following is a simple race scenario:
cpu0 cpu1
cleanup_net() [Round 1]
ops_undo_list()
xfrm_net_exit()
xfrm_nat_keepalive_net_fini()
cancel_delayed_work_sync(nat_keepalive_work);
xfrm_state_fini()
xfrm_state_flush()
xfrm_state_delete(x)
__xfrm_state_delete(x)
xfrm_nat_keepalive_state_updated(x)
schedule_delayed_work(nat_keepalive_work);
rcu_barrier();
net_complete_free();
net_passive_dec(net);
llist_add(&net->defer_free_list, &defer_free_list);
cleanup_net() [Round 2]
rcu_barrier();
net_complete_free()
kmem_cache_free(net_cachep, net);
nat_keepalive_work()
// on freed net
To prevent this, cancel_delayed_work_sync() is replaced with
disable_delayed_work_sync().
Severity
7.8 (High)
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae , < 32d0f44c2f14d60fe8e920e69a28c11051543ec1
(git)
Affected: f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae , < 2255ed6adbc3100d2c4a83abd9d0396d04b87792 (git) Affected: f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae , < 21f2fc49ca6faa393c31da33b8a4e6c41fc84c13 (git) Affected: f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae , < daf8e3b253aa760ff9e96c7768a464bc1d6b3c90 (git) |
guessed | |
| Linux | Linux |
Affected:
6.11
Unaffected: 0 , < 6.11 (semver) Unaffected: 6.12.80 , ≤ 6.12.* (semver) Unaffected: 6.18.21 , ≤ 6.18.* (semver) Unaffected: 6.19.11 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix) |
guessed |
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}
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}
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"url": "https://git.kernel.org/stable/c/daf8e3b253aa760ff9e96c7768a464bc1d6b3c90"
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini()\n\nAfter cancel_delayed_work_sync() is called from\nxfrm_nat_keepalive_net_fini(), xfrm_state_fini() flushes remaining\nstates via __xfrm_state_delete(), which calls\nxfrm_nat_keepalive_state_updated() to re-schedule nat_keepalive_work.\n\nThe following is a simple race scenario:\n\n cpu0 cpu1\n\ncleanup_net() [Round 1]\n ops_undo_list()\n xfrm_net_exit()\n xfrm_nat_keepalive_net_fini()\n cancel_delayed_work_sync(nat_keepalive_work);\n xfrm_state_fini()\n xfrm_state_flush()\n xfrm_state_delete(x)\n __xfrm_state_delete(x)\n xfrm_nat_keepalive_state_updated(x)\n schedule_delayed_work(nat_keepalive_work);\n rcu_barrier();\n net_complete_free();\n net_passive_dec(net);\n llist_add(\u0026net-\u003edefer_free_list, \u0026defer_free_list);\n\ncleanup_net() [Round 2]\n rcu_barrier();\n net_complete_free()\n kmem_cache_free(net_cachep, net);\n nat_keepalive_work()\n // on freed net\n\nTo prevent this, cancel_delayed_work_sync() is replaced with\ndisable_delayed_work_sync()."
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nxfrm: Corrige la reprogramaci\u00f3n del trabajo despu\u00e9s de la cancelaci\u00f3n en xfrm_nat_keepalive_net_fini()\n\nDespu\u00e9s de que se llama a cancel_delayed_work_sync() desde xfrm_nat_keepalive_net_fini(), xfrm_state_fini() vac\u00eda los estados restantes a trav\u00e9s de __xfrm_state_delete(), que llama a xfrm_nat_keepalive_state_updated() para reprogramar nat_keepalive_work.\n\nEl siguiente es un escenario de carrera simple:\n\n cpu0 cpu1\n\ncleanup_net() [Ronda 1]\n ops_undo_list()\n xfrm_net_exit()\n xfrm_nat_keepalive_net_fini()\n cancel_delayed_work_sync(nat_keepalive_work);\n xfrm_state_fini()\n xfrm_state_flush()\n xfrm_state_delete(x)\n __xfrm_state_delete(x)\n xfrm_nat_keepalive_state_updated(x)\n schedule_delayed_work(nat_keepalive_work);\n rcu_barrier();\n net_complete_free();\n net_passive_dec(net);\n llist_add(\u0026net -\u003e defer_free_list, \u0026defer_free_list);\n\ncleanup_net() [Ronda 2]\n rcu_barrier();\n net_complete_free()\n kmem_cache_free(net_cachep, net);\n nat_keepalive_work()\n // en net liberado\n\nPara evitar esto, cancel_delayed_work_sync() se reemplaza con disable_delayed_work_sync()."
}
],
"id": "CVE-2026-31406",
"lastModified": "2026-07-24T22:10:00.140",
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"scope": "UNCHANGED",
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"current_release_date": "2026-06-30T11:46:48+00:00",
"cve": "CVE-2026-31406",
"id": "CVE-2026-31406",
"initial_release_date": "2026-04-06T00:00:00+00:00",
"product_status:known_affected": "76",
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"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: xfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini()",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31406.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "important",
"current_release_date": "2026-09-11T01:32:42Z",
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"id": "CVE-2026-31406",
"initial_release_date": "2026-04-06T23:25:09Z",
"product_status:first_fixed": "2",
"product_status:known_not_affected": "395",
"product_status:recommended": "220",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-31406",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-31406.json",
"version": "14"
}
}
}
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
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- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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model, served locally by ML-Gateway.
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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