CVE-2026-23368: net: phy: register phy led_triggers during probe to avoid AB-BA deadlock
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 241cd64cf2e32b28ead151b1795cd8fef2b6e482, 2764dcb3c35de4410f642afc62cf979727470575, 2b01518eabace18f7ec8b4cafd52082303080dca; azl3 kernel 6.6.126.1-1 on Azure Linux 3.0 6.6.130.1-1; cbl2 kernel 5.15.202.1-1 on CBL-Mariner 2.0 Release Notes.
Low priority for now. Upgrade to Linux Linux 241cd64cf2e32b28ead151b1795cd8fef2b6e482, 2764dcb3c35de4410f642afc62cf979727470575, 2b01518eabace18f7ec8b4cafd52082303080dca; azl3 kernel 6.6.126.1-1 on Azure Linux 3.0 6.6.130.1-1; cbl2 kernel 5.15.202.1-1 on CBL-Mariner 2.0 Release Notes 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: net: phy: register phy led_triggers during probe to avoid AB-BA deadlock There is an AB-BA deadlock when both LEDS_TRIGGER_NETDEV and LED_TRIGGER_PHY are enabled: [ 1362.049207] [<8054e4b8>] led_trigger_register+0x5c/0x1fc <-- Trying to get lock "triggers_list_lock" via down_write(&triggers_list_lock); [ 1362.054536] [<80662830>] phy_led_triggers_register+0xd0/0x234 [ 1362.060329] [<8065e200>] phy_attach_direct+0x33c/0x40c [ 1362.065489] [<80651fc4>] phylink_fwnode_phy_connect+0x15c/0x23c [ 1362.071480] [<8066ee18>] mtk_open+0x7c/0xba0 [ 1362.075849] [<806d714c>] __dev_open+0x280/0x2b0 [ 1362.080384] [<806d7668>] __dev_change_flags+0x244/0x24c [ 1362.085598] [<806d7698>] dev_change_flags+0x28/0x78 [ 1362.090528] [<807150e4>] dev_ioctl+0x4c0/0x654 <-- Hold lock "rtnl_mutex" by calling rtnl_lock(); [ 1362.094985] [<80694360>] sock_ioctl+0x2f4/0x4e0 [ 1362.099567] [<802e9c4c>] sys_ioctl+0x32c/0xd8c [ 1362.104022] [<80014504>] syscall_common+0x34/0x58 Here LED_TRIGGER_PHY is registering LED triggers during phy_attach while holding RTNL and then taking triggers_list_lock. [ 1362.191101] [<806c2640>] register_netdevice_notifier+0x60/0x168 <-- Trying to get lock "rtnl_mutex" via rtnl_lock(); [ 1362.197073] [<805504ac>] netdev_trig_activate+0x194/0x1e4 [ 1362.202490] [<8054e28c>] led_trigger_set+0x1d4/0x360 <-- Hold lock "triggers_list_lock" by down_read(&triggers_list_lock); [ 1362.207511] [<8054eb38>] led_trigger_write+0xd8/0x14c [ 1362.212566] [<80381d98>] sysfs_kf_bin_write+0x80/0xbc [ 1362.217688] [<8037fcd8>] kernfs_fop_write_iter+0x17c/0x28c [ 1362.223174] [<802cbd70>] vfs_write+0x21c/0x3c4 [ 1362.227712] [<802cc0c4>] ksys_write+0x78/0x12c [ 1362.232164] [<80014504>] syscall_common+0x34/0x58 Here LEDS_TRIGGER_NETDEV is being enabled on an LED. It first takes triggers_list_lock and then RTNL. A classical AB-BA deadlock. phy_led_triggers_registers() does not require the RTNL, it does not make any calls into the network stack which require protection. There is also no requirement the PHY has been attached to a MAC, the triggers only make use of phydev state. This allows the call to phy_led_triggers_registers() to be placed elsewhere. PHY probe() and release() don't hold RTNL, so solving the AB-BA deadlock.
- Published
- Mar 25, 2026
- Updated
- Nov 5, 2026
- EPSS
- 0.1% · 0th percentile
- CWE
- CWE-667
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 kernel4.16.1 and later · before 5.10.253
- linux linux kernel5.11 and later · before 5.15.203
- linux linux kernel5.16 and later · before 6.1.167
- linux linux kernel6.2 and later · before 6.6.130
- linux linux kernel6.7 and later · before 6.12.78
- linux linux kernel6.13 and later · before 6.18.17
- linux linux kernel6.19 and later · before 6.19.7
- linux linux kernel4.16
- linux linux kernel7.0
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
- 4.16affected
- 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 and later · before 2b01518eabace18f7ec8b4cafd52082303080dcaaffected · git
- 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 and later · before 305afdd02ff3e694c165457793104710ec0728e5affected · git
- 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 and later · before c6ffc2d2338d325e1edd0c702e3ee623aa5fdc6aaffected · git
- 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 and later · before c33523b8fd2d4c504ada18cd93f511f2a8f84217affected · git
- 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 and later · before 241cd64cf2e32b28ead151b1795cd8fef2b6e482affected · git
- 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 and later · before 2764dcb3c35de4410f642afc62cf979727470575affected · git
- 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 and later · before cde2d0b5ab5d03b5b6f17d4f654d8b30ccf36757affected · git
- 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 and later · before c8dbdc6e380e7e96a51706db3e4b7870d8a9402daffected · git
- before 4.16not 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 6.1.170-1 | 6.1.170-1 |
| Debian:13 | linux | before 6.12.85-1 | 6.12.85-1 |
| Debian:14 | linux | before 6.19.8-1 | 6.19.8-1 |
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-2026-23366Mar 25, 2026 · drm/client: Do not destroy NULL modes22Monitor
- ← EarlierCVE-2026-23367Mar 25, 2026 · wifi: radiotap: reject radiotap with unknown bits22Monitor
- Later →CVE-2026-23369Mar 25, 2026 · i2c: i801: Revert "i2c: i801: replace acpi_lock with I2C bus lock"22Monitor
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 | 241cd64cf2e32b28ead151b1795cd8fef2b6e482 | Vendor (CNA) |
| Linux Linux | 2764dcb3c35de4410f642afc62cf979727470575 | Vendor (CNA) |
| Linux Linux | 2b01518eabace18f7ec8b4cafd52082303080dca | Vendor (CNA) |
| Linux Linux | 305afdd02ff3e694c165457793104710ec0728e5 | Vendor (CNA) |
| Linux Linux | c33523b8fd2d4c504ada18cd93f511f2a8f84217 | Vendor (CNA) |
| Linux Linux | c6ffc2d2338d325e1edd0c702e3ee623aa5fdc6a | Vendor (CNA) |
| Linux Linux | c8dbdc6e380e7e96a51706db3e4b7870d8a9402d | Vendor (CNA) |
| Linux Linux | cde2d0b5ab5d03b5b6f17d4f654d8b30ccf36757 | Vendor (CNA) |
| azl3 kernel 6.6.126.1-1 on Azure Linux 3.0 | 6.6.130.1-1 · CBL-Mariner Releases | Microsoft (MSRC) |
| cbl2 kernel 5.15.202.1-1 on CBL-Mariner 2.0 | Release Notes | Microsoft (MSRC) |
| debian:linux | 6.1.170-1 · 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-667 · Improper LockingCVSS 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.
Change log
- SSVC exploitation— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (11 more)Show less
- git.kernel.org/stable/c/2764dcb3c35de4410f642afc62cf979727470575
- git.kernel.org/stable/c/2b01518eabace18f7ec8b4cafd52082303080dca
- git.kernel.org/stable/c/305afdd02ff3e694c165457793104710ec0728e5
- git.kernel.org/stable/c/c33523b8fd2d4c504ada18cd93f511f2a8f84217
- git.kernel.org/stable/c/c6ffc2d2338d325e1edd0c702e3ee623aa5fdc6a
- git.kernel.org/stable/c/c8dbdc6e380e7e96a51706db3e4b7870d8a9402d
- git.kernel.org/stable/c/cde2d0b5ab5d03b5b6f17d4f654d8b30ccf36757
- cert-portal.siemens.com/productcert/html/ssa-019113.html
- cert-portal.siemens.com/productcert/html/ssa-082556.html
- cert-portal.siemens.com/productcert/html/ssa-457936.html
- cert-portal.siemens.com/productcert/html/ssa-784472.html
Vendor advisories and official records. Exploit/PoC links are deliberately left out.