CVE-2026-45915

MEDIUMNVD 5.55.5
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to NVD's CVSS score.

Score 5.5 from GitHub Security Advisory (severity: MODERATE) published 2026-05-27. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 3 sources updated this week

Also known asEUVD-2026-32381 (ENISA EUVD) · GHSA-2qhg-8p2v-wf99 (GitHub Security Advisories)Source: ENISA EUVD

5.5EG
EchelonGraph verdictMonitorRemediate within your standard update timelines (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 5.5Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

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

fat: avoid parent link count underflow in rmdir

Corrupted FAT images can leave a directory inode with an incorrect i_nlink (e.g. 2 even though subdirectories exist). rmdir then unconditionally calls drop_nlink(dir) and can drive i_nlink to 0, triggering the WARN_ON in drop_nlink().

Add a sanity check in vfat_rmdir() and msdos_rmdir(): only drop the parent link count when it is at least 3, otherwise report a filesystem error.

CVSS v3
5.5
EG Score
5.5MEDIUMmedium confidence
EG Risk
25
EG Risk 25/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity55% × 45%
Impact severity (EG Severity): CVSS 5.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.2% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.2%
EPSS %ILE
5th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (5.5): severity, escalated by confirmed exploitation. This CVE's 5.5 is its impact severity (EG Severity), not escalated.

EG Severity
5.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-05). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

May 27, 2026

Last Modified

November 6, 2026

Advisory Details (8)

Auto-updated Jun 24, 2026
Patch available.
Web page

fat: avoid parent link count underflow in rmdir - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d3b7ffa90f613938128432c7b2f35b7aa4bdd86b
Web page

fat: avoid parent link count underflow in rmdir - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d0bb592fa9def2bace90ac8926c0a1d6fa8c1aa0
Web page

fat: avoid parent link count underflow in rmdir - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/cd569b87378b9c33ae13c23d6bb9d205d66f7c4b
Web page

fat: avoid parent link count underflow in rmdir - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/9894c79fd9466612d0514be157b5c30cd93aa645
Web page

fat: avoid parent link count underflow in rmdir - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/955c5d670b5ae07c78f4345e23a895638db96ce1
Web page

fat: avoid parent link count underflow in rmdir - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/8cafcb881364af5ef3a8b9fed4db254054033d8a
Web page

fat: avoid parent link count underflow in rmdir - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/7fe0de287e931e07cb96ecf1f449b2ebdb0e1115
Web page

fat: avoid parent link count underflow in rmdir - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/17866f8a0822d414cb02e621cf003a7d04396ef8

Vendor Advisories for CVE-2026-45915(1)

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

Patch Availability(26)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntulinux-tools-oracle-lts-22.04 (5.15.0.1109.105) @ jammy2026-10-22ubuntu
ubuntulinux-xilinx-zynqmp (6.8.0.1032.33) @ noble2026-10-22ubuntu
ubuntulinux-tools-azure-lts-24.04 (6.8.0-1063.71) @ noble2026-10-22ubuntu
ubuntulinux-tools-intel-iot-realtime-5.15 (5.15.0.1104.108) @ jammy2026-10-22ubuntu
ubuntulinux-tools-intel-iotg-5.15 (5.15.0.1107.106) @ jammy2026-10-22ubuntu
ubuntulinux-tools-gcp-edge (5.15.0.1112.122~20.04.1) @ focal2026-10-22ubuntu
ubuntulinux-tools-raspi-realtime-6.8 (6.8.0-2049.50) @ noble2026-10-22ubuntu
ubuntulinux-tools-raspi-6.8 (6.8.0-1060.64) @ noble2026-10-22ubuntu
ubuntulinux-tools-nvidia-tegra-rt-5.15 (5.15.0.1064.66~20.04.1) @ focal2026-10-22ubuntu
ubuntulinux-tools-azure-fde-lts-24.04 (6.8.0-1062.69) @ noble2026-10-22ubuntu
ubuntulinux-tools-azure-fde-lts-22.04 (5.15.0.1117.126) @ jammy2026-10-22ubuntu
ubuntulinux-tools-azure-fips-5.15 (5.15.0.1117.102) @ jammy2026-10-22ubuntu
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1058.61.1) @ noble2026-10-22ubuntu
ubuntulinux-tools-nvidia-lowlatency-5.15 (5.15.0.1107.107) @ jammy2026-10-22ubuntu
ubuntulinux-virtual-6.8 (6.8.0-134.134) @ noble2026-10-22ubuntu
ubuntulinux-tools-lowlatency-hwe-20.04-edge (6.8.0-134.134.1) @ noble2026-10-22ubuntu
ubuntulinux-tools-nvidia-tegra-rt-6.8 (6.8.0-1029.30) @ noble2026-10-22ubuntu
ubuntulinux-tools-fips-6.8 (6.8.0-134.134+fips1) @ noble2026-10-22ubuntu
ubuntulinux-xilinx-zynqmp-tools-5.15.0-1075 (5.15.0-1075.79) @ jammy2026-10-22ubuntu
ubuntulinux-tools-ibm-edge (5.15.0.1106.110~20.04.1) @ focal2026-10-22ubuntu
ubuntulinux-tools-nvidia-tegra-rt-5.15 (5.15.0.1064.64) @ jammy2026-10-22ubuntu
ubuntulinux-tools-azure-fde-6.8 (6.8.0-1062.69~22.04.1) @ jammy2026-10-22ubuntu
ubuntulinux-virtual-hwe-22.04-edge (6.8.0-136.136~22.04.1) @ jammy2026-10-22ubuntu
ubuntulinux-tools-oracle-edge (5.15.0.1109.115~20.04.1) @ focal2026-10-22ubuntu
ubuntulinux-tools-raspi-nolpae (5.15.0.1106.104) @ jammy2026-10-22ubuntu
linuxKernel @ 5.10.252 (fixes >=2.6.19)—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

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
linux5.10.103-1 ... 5.10.92-2 (53 versions)
  • every version up to 5.10.257-1: fixed in 5.10.257-1
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.1.106-1 ... 6.1.99-1 (48 versions)
  • every version up to 6.1.170-1: fixed in 6.1.170-1
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.12.38-1 ... 6.12.85-1~bpo12+1 (17 versions)
  • every version up to 6.12.85-1: fixed in 6.12.85-1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.12.100-1 ... 6.18~rc7-1~exp1 (104 versions)
  • every version up to 6.18.14-1: fixed in 6.18.14-1
—

All Vendor Advisories

(25)

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 10× in last 7d / 43× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 256 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 156 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-06 16:38 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  2. 2026-11-06 16:30 UTCGHSA enrichmentGHSA-2qhg-8p2v-wf99 · GitHub severity MODERATE · GitHub CVSS 5.5
  3. 2026-11-06 16:05 UTCEG score recompute
  4. 2026-11-06 16:05 UTCGHSA enrichmentGHSA-2qhg-8p2v-wf99 · GitHub severity MODERATE · GitHub CVSS 5.5
  5. 2026-11-05 16:37 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  6. 2026-11-04 16:35 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  7. 2026-11-03 16:48 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  8. 2026-11-02 16:45 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  9. 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  10. 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  11. 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  12. 2026-10-30 15:25 UTCOSV refresh
  13. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  14. 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  15. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  16. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  17. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  18. 2026-10-25 14:25 UTCEG score recompute
  19. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  20. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  21. 2026-10-22 23:32 UTCEG score recompute
  22. 2026-10-22 23:32 UTCVendor advisory
  23. 2026-10-22 23:31 UTCGHSA enrichmentGHSA-2qhg-8p2v-wf99 · GitHub CVSS 5.5
  24. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  25. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.2% · 5th percentile
Show 75 more
  1. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  2. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  3. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  4. 2026-10-18 03:37 UTCEG score recompute
  5. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  6. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  7. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  8. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  9. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  10. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  11. 2026-10-12 16:03 UTCEG score recompute
  12. 2026-10-11 19:46 UTCEG score recompute
  13. 2026-10-11 17:00 UTCEG score recompute
  14. 2026-10-11 14:25 UTCEG score recompute
  15. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  16. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  17. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  18. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  19. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  20. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  21. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  22. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  23. 2026-10-03 18:51 UTCOSV refresh
  24. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  25. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  26. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  27. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  28. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  29. 2026-09-23 17:53 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  30. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  31. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  32. 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  33. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  34. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  35. 2026-09-14 09:02 UTCEG score recompute
  36. 2026-09-14 09:02 UTCVendor advisory
  37. 2026-09-14 09:01 UTCGHSA enrichmentGHSA-2qhg-8p2v-wf99 · GitHub CVSS 5.5
  38. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  39. 2026-09-13 04:09 UTCOSV refresh
  40. 2026-09-12 15:01 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  41. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  42. 2026-09-11 09:37 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  43. 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  44. 2026-09-08 22:00 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  45. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  46. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  47. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  48. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  49. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  50. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  51. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  52. 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  53. 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  54. 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  55. 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  56. 2026-08-25 05:44 UTCEG score recompute
  57. 2026-08-25 05:44 UTCVendor advisory
  58. 2026-08-25 05:43 UTCGHSA enrichmentGHSA-2qhg-8p2v-wf99 · GitHub CVSS 5.5
  59. 2026-08-23 15:30 UTCEG score recompute
  60. 2026-08-23 15:30 UTCVendor advisory
  61. 2026-08-23 15:29 UTCGHSA enrichmentGHSA-2qhg-8p2v-wf99 · GitHub CVSS 5.5
  62. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  63. 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  64. 2026-08-21 20:52 UTCVendor advisory
  65. 2026-08-21 20:52 UTCGHSA enrichmentGHSA-2qhg-8p2v-wf99 · GitHub CVSS 5.5
  66. 2026-08-20 17:41 UTCEG score recompute
  67. 2026-08-20 17:41 UTCVendor advisory
  68. 2026-08-20 17:40 UTCGHSA enrichmentGHSA-2qhg-8p2v-wf99 · GitHub CVSS 5.5
  69. 2026-08-19 17:04 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  70. 2026-08-18 13:48 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  71. 2026-08-17 13:47 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  72. 2026-08-17 09:21 UTCEG score recompute
  73. 2026-08-17 09:21 UTCVendor advisory
  74. 2026-08-17 09:21 UTCGHSA enrichmentGHSA-2qhg-8p2v-wf99 · GitHub CVSS 5.5
  75. 2026-08-16 14:56 UTCEPSS rescoreEPSS 0.2% · 5th percentile

Frequently asked(5)

What is CVE-2026-45915?
CVE-2026-45915 is a medium-severity vulnerability; its CVE record was published on May 27, 2026. In the Linux kernel, the following vulnerability has been resolved: fat: avoid parent link count underflow in rmdir Corrupted FAT images can leave a directory inode with an incorrect i_nlink (e.g. 2 even though subdirectories exist). rmdir then unconditionally calls drop_nlink(dir) and can drive…
When was the CVE record for CVE-2026-45915 published?
The CVE record for CVE-2026-45915 was published on May 27, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of November 6, 2026; the record at its source may have been updated since.
Is CVE-2026-45915 actively exploited?
CVE-2026-45915 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (5th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-45915?
CVE-2026-45915 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-45915?
A fix for CVE-2026-45915 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-45915 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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