CVE-2026-46107

HIGHPre-NVD 7.87.8—
EchelonGraph scoreMEDIUM confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2026-05-28. a secondary CVSS source baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
7.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.8Exploit: None knownExposed: 0

A fix is available — apply it.

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

dm-thin: fix metadata refcount underflow

There's a bug in dm-thin in the function rebalance_children. If the internal btree node has one entry, the code tries to copy all btree entries from the node's child to the node itself and then decrement the child's reference count.

If the child node is shared (it has reference count > 1), we won't free it, so there would be two pointers to each of the grandchildren nodes. But the reference counts of the grandchildren is not increased, thus the reference count doesn't match the number of pointers that point to the grandchildren. This results in "device mapper: space map common: unable to decrement block" errors.

Fix this bug by incrementing reference counts on the grandchildren if the btree node is shared.

CVSS v3
7.8
EG Score
7.8(medium)
EG Risk
40(Track)
EG Risk 40/100SSVC: 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
Severity78% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
3%
KEV
Not listed

Published

May 28, 2026

Last Modified

June 25, 2026

Advisory Details (7)

Auto-updated Jun 3, 2026
No patch confirmed yet.
generic

dm-thin: fix metadata refcount underflow - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/f49b41c9eb7c6ff00df27cd49cea210abbadd8ad
generic

dm-thin: fix metadata refcount underflow - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/f06f6aededd792a754cd677c02b3d3016d868c2c
generic

dm-thin: fix metadata refcount underflow - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/85311a585a26640760cd0f3349ab9f2905691044
generic

dm-thin: fix metadata refcount underflow - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/5ec0debbcfd43596e32c1239e993de06a704e04c
generic

dm-thin: fix metadata refcount underflow - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/323d252a4a378834e4fe68298ca61cfc5dd3a460
generic

dm-thin: fix metadata refcount underflow - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/12161e03d33afce781f68fa11cc6060538862fad
generic

dm-thin: fix metadata refcount underflow - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/09a65adc7d8bbfce06392cb6d375468e2728ead5

Vendor Advisories for CVE-2026-46107(2)

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

Patch Availability(22)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-virtual-hwe-26.04-edge (7.0.0-28.28) @ resolute2026-07-27ubuntu
ubuntulinux-virtual-6.8 (6.8.0-136.136) @ noble2026-07-27ubuntu
ubuntulinux-tools-oem-7.0 (7.0.0-1009.9) @ resolute2026-07-27ubuntu
ubuntulinux-virtual-hwe-24.04-edge (7.0.0-28.28~24.04.1) @ noble2026-07-27ubuntu
ubuntulinux-tools-nvidia-tegra-rt-5.15 (5.15.0.1064.66~20.04.1) @ focal2026-07-27ubuntu
ubuntulinux-tools-gcp-fips-6.8 (6.8.0-1064.72+fips1) @ noble2026-07-27ubuntu
ubuntulinux-virtual-hwe-20.04-edge (5.15.0.186.196~20.04.1) @ focal2026-07-27ubuntu
ubuntulinux-tools-oracle-7.0 (7.0.0-1008.8) @ resolute2026-07-27ubuntu
ubuntulinux-tools-oracle-lts-24.04 (6.8.0-1058.61) @ noble2026-07-27ubuntu
ubuntulinux-tools-oracle-lts-22.04 (5.15.0.1109.105) @ jammy2026-07-27ubuntu
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1059.62.1) @ noble2026-07-27ubuntu
ubuntulinux-tools-oracle-edge (6.8.0-1058.61~22.04.1) @ jammy2026-07-27ubuntu
ubuntulinux-tools-ibm-edge (5.15.0.1106.110~20.04.1) @ focal2026-07-27ubuntu
ubuntulinux-tools-aws-lts-24.04 (6.8.0-1061.64+1) @ noble2026-07-27ubuntu
ubuntulinux-tools-nvidia-tegra-rt-5.15 (5.15.0.1064.64) @ jammy2026-07-27ubuntu
ubuntulinux-tools-nvidia-lowlatency-5.15 (5.15.0.1107.107) @ jammy2026-07-27ubuntu
ubuntulinux-tools-azure-fde-7.0 (7.0.0-1009.9) @ resolute2026-07-27ubuntu
ubuntulinux-tools-azure-lts-24.04 (6.8.0-1063.71) @ noble2026-07-27ubuntu
ubuntulinux-tools-azure-fde-lts-24.04 (6.8.0-1062.69) @ noble2026-07-27ubuntu
ubuntulinux-tools-azure-fips-6.8 (6.8.0-1063.71+fips2) @ noble2026-07-27ubuntu
ubuntulinux-tools-azure-fde-6.8 (6.8.0-1062.69~22.04.1) @ jammy2026-07-27ubuntu
ubuntulinux-tools-azure-fde-lts-22.04 (5.15.0.1117.126) @ jammy2026-07-27ubuntu

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.

Weakness Classification(1)

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

Additional Vendor Advisories

(22)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 12× in last 7d / 50× 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 166 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-46107?
CVE-2026-46107 is a high vulnerability published on May 28, 2026. In the Linux kernel, the following vulnerability has been resolved: dm-thin: fix metadata refcount underflow There's a bug in dm-thin in the function rebalance_children. If the internal btree node has one entry, the code tries to copy all btree entries from the node's child to the node itself and…
When was CVE-2026-46107 disclosed?
CVE-2026-46107 was first published in the National Vulnerability Database on May 28, 2026, with the most recent update on June 25, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-46107 actively exploited?
CVE-2026-46107 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 97.0% of all scored CVEs.
What is the CVSS score of CVE-2026-46107?
CVE-2026-46107 has a CVSS v3 base score of 7.8 (NVD).
How do I remediate CVE-2026-46107?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-46107, 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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