CVE-2026-23124: ipv6: annotate data-race in ndisc_router_discovery()
Noroxi assessment
Priority: Monitor (action score 22/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.10% (FIRST EPSS).
- Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: Linux Linux 2619499169fb1c2ac4974b0f2d87767fb543582b, 2a2b9d25f801afecf2f83cacce98afa8fd73e3c9, 4630897eb1a039b5d7b737b8dc9521d9d4b568b5.
Low priority for now. Upgrade to Linux Linux 2619499169fb1c2ac4974b0f2d87767fb543582b, 2a2b9d25f801afecf2f83cacce98afa8fd73e3c9, 4630897eb1a039b5d7b737b8dc9521d9d4b568b5 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
In the Linux kernel, the following vulnerability has been resolved: ipv6: annotate data-race in ndisc_router_discovery() syzbot found that ndisc_router_discovery() could read and write in6_dev->ra_mtu without holding a lock [1] This looks fine, IFLA_INET6_RA_MTU is best effort. Add READ_ONCE()/WRITE_ONCE() to document the race. Note that we might also reject illegal MTU values (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) in a future patch. [1] BUG: KCSAN: data-race in ndisc_router_discovery / ndisc_router_discovery read to 0xffff888119809c20 of 4 bytes by task 25817 on cpu 1: ndisc_router_discovery+0x151d/0x1c90 net/ipv6/ndisc.c:1558 ndisc_rcv+0x2ad/0x3d0 net/ipv6/ndisc.c:1841 icmpv6_rcv+0xe5a/0x12f0 net/ipv6/icmp.c:989 ip6_protocol_deliver_rcu+0xb2a/0x10d0 net/ipv6/ip6_input.c:438 ip6_input_finish+0xf0/0x1d0 net/ipv6/ip6_input.c:489 NF_HOOK include/linux/netfilter.h:318 [inline] ip6_input+0x5e/0x140 net/ipv6/ip6_input.c:500 ip6_mc_input+0x27c/0x470 net/ipv6/ip6_input.c:590 dst_input include/net/dst.h:474 [inline] ip6_rcv_finish+0x336/0x340 net/ipv6/ip6_input.c:79 ... write to 0xffff888119809c20 of 4 bytes by task 25816 on cpu 0: ndisc_router_discovery+0x155a/0x1c90 net/ipv6/ndisc.c:1559 ndisc_rcv+0x2ad/0x3d0 net/ipv6/ndisc.c:1841 icmpv6_rcv+0xe5a/0x12f0 net/ipv6/icmp.c:989 ip6_protocol_deliver_rcu+0xb2a/0x10d0 net/ipv6/ip6_input.c:438 ip6_input_finish+0xf0/0x1d0 net/ipv6/ip6_input.c:489 NF_HOOK include/linux/netfilter.h:318 [inline] ip6_input+0x5e/0x140 net/ipv6/ip6_input.c:500 ip6_mc_input+0x27c/0x470 net/ipv6/ip6_input.c:590 dst_input include/net/dst.h:474 [inline] ip6_rcv_finish+0x336/0x340 net/ipv6/ip6_input.c:79 ... value changed: 0x00000000 -> 0xe5400659
- Published
- Feb 14, 2026
- Updated
- Oct 19, 2026
- EPSS
- 0.1% · 1th percentile
- CWE
- CWE-362
Report tools
Action score
22
Monitor
Low priority for now.
- CVSS
- 22 / 40 · 5.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| linux | linux kernel | cpe:2.3:o:linux:linux_kernel |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- linux linux kernel5.15 and later · before 5.15.199
- linux linux kernel5.16 and later · before 6.1.162
- linux linux kernel6.2 and later · before 6.6.122
- linux linux kernel6.7 and later · before 6.12.68
- linux linux kernel6.13 and later · before 6.18.8
- linux linux kernel6.19
Versions reported by the vendor
Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.
Linux Linux
- 5.15affected
- 49b99da2c9ce13ffcd93fe3a0f5670791c1d76f7 and later · before 4630897eb1a039b5d7b737b8dc9521d9d4b568b5affected · git
- 49b99da2c9ce13ffcd93fe3a0f5670791c1d76f7 and later · before 2619499169fb1c2ac4974b0f2d87767fb543582baffected · git
- 49b99da2c9ce13ffcd93fe3a0f5670791c1d76f7 and later · before fad8f4ff7928f4d52a062ffdcffa484989c79c47affected · git
- 49b99da2c9ce13ffcd93fe3a0f5670791c1d76f7 and later · before 2a2b9d25f801afecf2f83cacce98afa8fd73e3c9affected · git
- 49b99da2c9ce13ffcd93fe3a0f5670791c1d76f7 and later · before e3c1040252e598f7b4e33a42dc7c38519bc22428affected · git
- 49b99da2c9ce13ffcd93fe3a0f5670791c1d76f7 and later · before 9a063f96d87efc3a6cc667f8de096a3d38d74bb5affected · git
- before 5.15not affected · semver
- 5.15.199 and later · up to and including 5.15.*not affected · semver
- 6.1.162 and later · up to and including 6.1.*not affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | linux | before 6.1.162-1 | 6.1.162-1 |
| Debian:13 | linux | before 6.12.69-1 | 6.12.69-1 |
| Debian:14 | linux | before 6.18.8-1 | 6.18.8-1 |
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV90Now
- CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV89Now
- CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV85Now
Published before and after this one in the same product
- ← EarlierCVE-2026-23120Feb 14, 2026 · l2tp: avoid one data-race in l2tp_tunnel_del_work()22Monitor
- ← EarlierCVE-2026-23121Feb 14, 2026 · mISDN: annotate data-race around dev->work22Monitor
- Later →CVE-2026-23125Feb 14, 2026 · sctp: move SCTP_CMD_ASSOC_SHKEY right after SCTP_CMD_PEER_INIT22Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Linux Linux | 2619499169fb1c2ac4974b0f2d87767fb543582b | Vendor (CNA) |
| Linux Linux | 2a2b9d25f801afecf2f83cacce98afa8fd73e3c9 | Vendor (CNA) |
| Linux Linux | 4630897eb1a039b5d7b737b8dc9521d9d4b568b5 | Vendor (CNA) |
| Linux Linux | 9a063f96d87efc3a6cc667f8de096a3d38d74bb5 | Vendor (CNA) |
| Linux Linux | e3c1040252e598f7b4e33a42dc7c38519bc22428 | Vendor (CNA) |
| Linux Linux | fad8f4ff7928f4d52a062ffdcffa484989c79c47 | Vendor (CNA) |
| debian:linux | 6.1.162-1 · Debian:12 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-362 · Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (5 more)Show less
- git.kernel.org/stable/c/2a2b9d25f801afecf2f83cacce98afa8fd73e3c9
- git.kernel.org/stable/c/4630897eb1a039b5d7b737b8dc9521d9d4b568b5
- git.kernel.org/stable/c/9a063f96d87efc3a6cc667f8de096a3d38d74bb5
- git.kernel.org/stable/c/e3c1040252e598f7b4e33a42dc7c38519bc22428
- git.kernel.org/stable/c/fad8f4ff7928f4d52a062ffdcffa484989c79c47
Vendor advisories and official records. Exploit/PoC links are deliberately left out.