CVE-2026-74398: ipv6: addrconf: bail out of dad_failure when state is no longer POSTDAD
- Is it exploited?
Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of . If CISA adds it, this page shows it as known exploited.
- How likely is exploitation in the next 30 days?
- 0.5%
EPSS score, percentile 43.7 of all scored records. A probability estimated by FIRST, not a report of exploitation.
- How severe?
- 9.8 Critical
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA has set no required action, because the vulnerability is not in KEV.
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Affected
- from 3.10.105 to before 3.11
- 3.14
Unaffected before 3.14; 5.10.261; 5.15.212; 6.1.178; 6.6.145; 6.12.97; and 3 more
Source: CISA KEV 2026.10.29, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.
What to do
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | from c15b1ccadb32 to before 47b05836705b |
| Affected | from c15b1ccadb32 to before d21be7d05101 |
| Affected | from c15b1ccadb32 to before 875c284c0f98 |
| Affected | from c15b1ccadb32 to before 8ed0ce9ea58d |
| Affected | from c15b1ccadb32 to before 3bdc86d89fd6 |
| Affected | from c15b1ccadb32 to before b61af0268e3d |
| Affected | from c15b1ccadb32 to before e889aa99ad3e |
| Affected | from c15b1ccadb32 to before 627ac78f2741 |
| Affected | 835b474b8f70 |
| Affected | from 3.10.105 to before 3.11 |
Versions not listed are: unaffected.
| Status | Versions |
|---|---|
| Affected | 3.14 |
| Unaffected | before 3.14 |
| Unaffected | 5.10.261 |
| Unaffected | 5.15.212 |
| Unaffected | 6.1.178 |
| Unaffected | 6.6.145 |
| Unaffected | 6.12.97 |
| Unaffected | 6.18.40 |
| Unaffected | 7.1.5 |
| Unaffected | 7.2 |
Versions not listed are: affected.
Versions the record lists as unaffected: 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.97, 6.18.40, 7.1.5, 7.2.
Source: CVE List, as of . About the data.
About this vulnerability
In the Linux kernel, the following vulnerability has been resolved: ipv6: addrconf: bail out of dad_failure when state is no longer POSTDAD addrconf_dad_failure() transitions ifp->state from DAD to POSTDAD via addrconf_dad_end(), which drops ifp->lock on return. The lock is re-acquired after net_info_ratelimited(). A concurrent ipv6_del_addr() can take the lock in that window, set ifp->state…
Summary: CVE record, as of .
- CISA has not added CVE-2026-74398 to its Known Exploited Vulnerabilities (KEV) catalog, as of 29 Oct 2026.
- The CVE record was published on 15 Aug 2026.
- The CVE record carries a CVSS v3.1 base score of 9.8 (Critical), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 0.5% (percentile 43.7), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
- CISA's SSVC assessment in the CVE record: exploitation none, automatable yes, technical impact total.
Source: CISA KEV 2026.10.29, as of ; CVE List, as of ; FIRST EPSS, as of . About the data.
Description
ipv6: addrconf: bail out of dad_failure when state is no longer POSTDAD
In the Linux kernel, the following vulnerability has been resolved: ipv6: addrconf: bail out of dad_failure when state is no longer POSTDAD addrconf_dad_failure() transitions ifp->state from DAD to POSTDAD via addrconf_dad_end(), which drops ifp->lock on return. The lock is re-acquired after net_info_ratelimited(). A concurrent ipv6_del_addr() can take the lock in that window, set ifp->state to DEAD and run list_del_rcu(&ifp->if_list). addrconf_dad_failure() then overwrites DEAD with ERRDAD at errdad: and schedules a new dad_work. The work calls ipv6_del_addr() again, hitting the already-poisoned list entry: general protection fault: 0000 [#1] SMP NOPTI CPU: 4 PID: 217 Comm: kworker/4:1 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:ipv6_del_addr+0xe9/0x280 RAX: dead000000000122 Call Trace: addrconf_dad_stop+0x113/0x140 addrconf_dad_work+0x28c/0x430 process_one_work+0x1eb/0x3b0 worker_thread+0x4d/0x400 kthread+0x104/0x140 ret_from_fork+0x35/0x40 Fold the addrconf_dad_end() logic into addrconf_dad_failure() under a single ifp->lock critical section. The STABLE_PRIVACY branch temporarily drops ifp->lock around address regeneration, so at lock_errdad: verify the state is still POSTDAD before transitioning to ERRDAD; bail out otherwise to avoid overwriting a state set by another path while the lock was released.
Source: CVE List, as of . About the data.
Timeline
| Date | Event |
|---|---|
| CVE record published | |
| CVE record last updated |
References
8
Known exploited Linux vulnerabilities
- CVE-2026-46300: Linux Kernel Missing Initialization of a Variable Vulnerability
- CVE-2025-39682: Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability
- CVE-2025-39964: Linux Kernel Race Condition Vulnerability
- CVE-2026-53266: Linux Kernel Out-of-Bounds Write Vulnerability
- CVE-2026-53362: Linux Kernel Unspecified Vulnerability