CVE-2026-43421

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-05-08. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
5.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: None knownExposed: 0

A fix is available — apply it.

In the Linux kernel, the following vulnerability has been resolved:

usb: gadget: f_ncm: Fix net_device lifecycle with device_move

The network device outlived its parent gadget device during disconnection, resulting in dangling sysfs links and null pointer dereference problems.

A prior attempt to solve this by removing SET_NETDEV_DEV entirely [1] was reverted due to power management ordering concerns and a NO-CARRIER regression.

A subsequent attempt to defer net_device allocation to bind [2] broke 1:1 mapping between function instance and network device, making it impossible for configfs to report the resolved interface name. This results in a regression where the DHCP server fails on pmOS.

Use device_move to reparent the net_device between the gadget device and /sys/devices/virtual/ across bind/unbind cycles. This preserves the network interface across USB reconnection, allowing the DHCP server to retain their binding.

Introduce gether_attach_gadget()/gether_detach_gadget() helpers and use __free(detach_gadget) macro to undo attachment on bind failure. The bind_count ensures device_move executes only on the first bind.

[1] https://lore.kernel.org/lkml/[email protected]/ [2] https://lore.kernel.org/linux-usb/[email protected]/

CVSS v3
5.5
EG Score
5.5(medium)
EG Risk
29(Track)
EG Risk 29/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity55% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
2%
KEV
Not listed

Published

May 8, 2026

Last Modified

June 19, 2026

Advisory Details (4)

Auto-updated Jun 16, 2026
No patch confirmed yet.
generic

usb: gadget: f_ncm: Fix net_device lifecycle with device_move - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/ec35c1969650e7cb6c8a91020e568ed46e3551b0
generic

usb: gadget: f_ncm: Fix net_device lifecycle with device_move - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/e584cb58a2ea7ff4d3a4bc43d5ca512ed3ecb77d
generic

usb: gadget: f_ncm: Fix net_device lifecycle with device_move - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/93f116c3393a22acab96ad1bef12b2572eb80ca4
generic

usb: gadget: f_ncm: Fix net_device lifecycle with device_move - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/85acaba2f42b557499bab3608307f17bf13beb69

Vendor Advisories for CVE-2026-43421(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(15)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-tools-azure-fde-6.8 (6.8.0-1062.69~22.04.1) @ jammy2026-08-23ubuntu
ubuntulinux-tools-aws-fips-6.8 (6.8.0-1061.64+fips1) @ noble2026-08-23ubuntu
ubuntulinux-tools-oracle-lts-24.04 (6.8.0-1058.61) @ noble2026-08-23ubuntu
ubuntulinux-tools-gcp-fips-6.8 (6.8.0-1064.72+fips1) @ noble2026-08-23ubuntu
ubuntulinux-tools-aws-lts-24.04 (6.8.0-1061.64+1) @ noble2026-08-23ubuntu
ubuntulinux-tools-oracle-edge (6.8.0-1058.61~22.04.1) @ jammy2026-08-23ubuntu
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1059.62.1) @ noble2026-08-23ubuntu
ubuntulinux-virtual-6.8 (6.8.0-136.136) @ noble2026-08-23ubuntu
ubuntulinux-tools-raspi-realtime-6.8 (6.8.0-2050.52) @ noble2026-08-23ubuntu
ubuntulinux-tools-azure-edge (6.8.0-1063.71~22.04.1) @ jammy2026-08-23ubuntu
ubuntulinux-tools-azure-fde-lts-24.04 (6.8.0-1062.69) @ noble2026-08-23ubuntu
ubuntulinux-tools-azure-fips-6.8 (6.8.0-1063.71+fips2) @ noble2026-08-23ubuntu
ubuntulinux-virtual-hwe-22.04-edge (6.8.0-136.136~22.04.1) @ jammy2026-08-23ubuntu
ubuntulinux-xilinx-zynqmp (6.8.0.1033.34) @ noble2026-08-23ubuntu
linuxKernel @ 6.1.176—osv

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(5 across 4 ecosystems)
Debian:11(2)
PackageVulnerable rangeFixed inDependents
linux5.10.103-1 ... 7.2~rc5-1~exp1 (496 versions)——
linux-6.16.1.106-3~deb11u1 ... 6.1.174-1~deb11u1 (20 versions)6.1.176-1~deb11u1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 6.1.99-1 (53 versions)6.1.176-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.85-1~bpo12+1 (17 versions)6.12.85-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 6.19~rc8-1~exp1 (119 versions)6.19.10-1—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(14)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 5× in last 7d / 55× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 174 total refreshes for this CVE.

  1. 2026-09-04 05:06 UTCEPSS rescore
  2. 2026-09-02 14:12 UTCEPSS rescore
  3. 2026-09-01 13:54 UTCEPSS rescore
  4. 2026-08-30 19:17 UTCEPSS rescore
  5. 2026-08-30 01:22 UTCEPSS rescore
  6. 2026-08-28 21:41 UTCEPSS rescore
  7. 2026-08-27 14:25 UTCEPSS rescore
  8. 2026-08-26 14:46 UTCEPSS rescore
  9. 2026-08-25 13:49 UTCEPSS rescore
  10. 2026-08-23 19:06 UTCEG score recompute
  11. 2026-08-23 19:06 UTCVendor advisory
  12. 2026-08-23 19:06 UTCGHSA enrichment
  13. 2026-08-23 00:19 UTCEPSS rescore
  14. 2026-08-21 23:49 UTCEPSS rescore
  15. 2026-08-20 22:55 UTCEPSS rescore
  16. 2026-08-19 17:04 UTCEPSS rescore
  17. 2026-08-18 13:48 UTCEPSS rescore
  18. 2026-08-17 13:47 UTCEPSS rescore
  19. 2026-08-17 11:31 UTCEG score recompute
  20. 2026-08-17 11:31 UTCVendor advisory
  21. 2026-08-17 11:31 UTCGHSA enrichment
  22. 2026-08-16 14:56 UTCEPSS rescore
  23. 2026-08-16 04:35 UTCEG score recompute
  24. 2026-08-16 04:35 UTCVendor advisory
  25. 2026-08-16 04:35 UTCGHSA enrichment
Show 75 more
  1. 2026-08-16 02:14 UTCEPSS rescore
  2. 2026-08-15 01:30 UTCEPSS rescore
  3. 2026-08-14 03:08 UTCEG score recompute
  4. 2026-08-14 03:08 UTCVendor advisory
  5. 2026-08-14 03:08 UTCGHSA enrichment
  6. 2026-08-13 22:00 UTCEPSS rescore
  7. 2026-08-12 16:44 UTCEG score recompute
  8. 2026-08-12 16:44 UTCVendor advisory
  9. 2026-08-12 16:44 UTCGHSA enrichment
  10. 2026-08-12 13:51 UTCEPSS rescore
  11. 2026-08-11 13:43 UTCEPSS rescore
  12. 2026-08-11 08:32 UTCEG score recompute
  13. 2026-08-11 08:32 UTCVendor advisory
  14. 2026-08-11 08:32 UTCGHSA enrichment
  15. 2026-08-11 00:00 UTCEPSS rescore
  16. 2026-08-10 06:50 UTCEG score recompute
  17. 2026-08-10 06:50 UTCVendor advisory
  18. 2026-08-10 06:50 UTCGHSA enrichment
  19. 2026-08-09 13:46 UTCEPSS rescore
  20. 2026-08-09 05:07 UTCEG score recompute
  21. 2026-08-09 05:07 UTCVendor advisory
  22. 2026-08-09 05:07 UTCGHSA enrichment
  23. 2026-08-08 16:37 UTCEPSS rescore
  24. 2026-08-08 03:25 UTCEG score recompute
  25. 2026-08-08 03:25 UTCVendor advisory
  26. 2026-08-08 03:25 UTCGHSA enrichment
  27. 2026-08-07 01:43 UTCEG score recompute
  28. 2026-08-07 01:43 UTCVendor advisory
  29. 2026-08-07 01:43 UTCGHSA enrichment
  30. 2026-08-06 13:46 UTCEPSS rescore
  31. 2026-08-05 22:08 UTCEG score recompute
  32. 2026-08-05 22:08 UTCVendor advisory
  33. 2026-08-05 22:08 UTCGHSA enrichment
  34. 2026-08-05 19:17 UTCEPSS rescore
  35. 2026-08-04 15:10 UTCEPSS rescore
  36. 2026-08-04 10:38 UTCEPSS rescore
  37. 2026-08-03 10:36 UTCEPSS rescore
  38. 2026-08-03 04:31 UTCVendor advisory
  39. 2026-08-03 04:31 UTCGHSA enrichment
  40. 2026-08-02 02:48 UTCEG score recompute
  41. 2026-08-02 02:48 UTCVendor advisory
  42. 2026-08-02 02:48 UTCGHSA enrichment
  43. 2026-08-02 02:27 UTCEPSS rescore
  44. 2026-08-01 04:16 UTCEPSS rescore
  45. 2026-07-30 16:28 UTCEPSS rescore
  46. 2026-07-30 01:30 UTCEPSS rescore
  47. 2026-07-28 15:36 UTCEPSS rescore
  48. 2026-07-27 14:13 UTCEPSS rescore
  49. 2026-07-26 14:54 UTCEPSS rescore
  50. 2026-07-26 14:54 UTCEPSS rescore
  51. 2026-07-25 14:18 UTCEPSS rescore
  52. 2026-07-24 14:17 UTCEPSS rescore
  53. 2026-07-23 14:18 UTCEPSS rescore
  54. 2026-07-23 03:14 UTCEG score recompute
  55. 2026-07-22 14:08 UTCEPSS rescore
  56. 2026-07-21 15:24 UTCEPSS rescore
  57. 2026-07-20 17:08 UTCEPSS rescore
  58. 2026-07-19 14:31 UTCEPSS rescore
  59. 2026-07-19 02:29 UTCEPSS rescore
  60. 2026-07-18 10:04 UTCEPSS rescore
  61. 2026-07-16 17:03 UTCEPSS rescore
  62. 2026-07-16 05:23 UTCOSV refresh
  63. 2026-07-15 16:57 UTCEPSS rescore
  64. 2026-07-15 02:00 UTCEPSS rescore
  65. 2026-07-13 22:30 UTCEPSS rescore
  66. 2026-07-13 06:13 UTCEPSS rescore
  67. 2026-07-12 05:46 UTCEPSS rescore
  68. 2026-07-11 08:27 UTCEPSS rescore
  69. 2026-07-09 19:10 UTCEPSS rescore
  70. 2026-07-08 15:16 UTCEPSS rescore
  71. 2026-07-07 13:46 UTCEPSS rescore
  72. 2026-07-06 16:27 UTCEPSS rescore
  73. 2026-07-06 02:23 UTCEPSS rescore
  74. 2026-07-05 02:30 UTCEPSS rescore
  75. 2026-07-04 06:31 UTCEPSS rescore

Frequently asked(5)

What is CVE-2026-43421?
CVE-2026-43421 is a medium vulnerability published on May 8, 2026. In the Linux kernel, the following vulnerability has been resolved: usb: gadget: fncm: Fix netdevice lifecycle with device_move The network device outlived its parent gadget device during disconnection, resulting in dangling sysfs links and null pointer dereference problems. A prior attempt to…
When was CVE-2026-43421 disclosed?
CVE-2026-43421 was first published in the National Vulnerability Database on May 8, 2026, with the most recent update on June 19, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-43421 actively exploited?
CVE-2026-43421 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 97.7% of all scored CVEs.
What is the CVSS score of CVE-2026-43421?
CVE-2026-43421 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-43421?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-43421, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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