CVE-2026-2340

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreMEDIUM confidence

Score 6.5 from GitHub Security Advisory published 2026-05-27. a secondary CVSS source baseline 6.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 6.5Exploit: None knownExposed: 0

A fix is available — apply it.

A flaw was found in Samba’s vfs_worm module. The module is intended to provide write-once, read-many (WORM) protections by preventing modification of files after a configurable grace period. Due to insufficient validation during rename operations, an authenticated user with write access to a share could overwrite a protected file by renaming a newly created file over the existing WORM-protected file.

CVSS v3
6.5
EG Score
6.5(medium)
EG Risk
30(Track)
EG Risk 30/100SSVC: 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
Severity65% × 45%
Exploitation1% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
58%
KEV
Not listed

Published

May 27, 2026

Last Modified

August 26, 2026

Advisory Details (5)

Auto-updated Jun 12, 2026
Patch available. Sources: redhat.
generic

15997 – (CVE-2026-2340) [SECURITY] CVE-2026-2340 vfs_worm does not block file overwrite

https://bugzilla.samba.org/show_bug.cgi?id=15997
redhat Patch Available

2447318 – (CVE-2026-2340) CVE-2026-2340 samba: vfs_worm does not block directory modification

Affected: Red Hat Enterprise Linux 10

https://bugzilla.redhat.com/show_bug.cgi?id=2447318
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-2340
redhat Patch Available

Affected: Red Hat Enterprise Linux 9.

https://access.redhat.com/errata/RHSA-2026:25049
redhat Patch Available

Affected: Red Hat Enterprise Linux 10.

https://access.redhat.com/errata/RHSA-2026:22963

Vendor Advisories for CVE-2026-2340(12)

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

Patch Availability(11)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntuwinbind (2:4.23.6+dfsg-1ubuntu2.1) @ resolute2026-08-26ubuntu
redhatrhcos-4.19.9.6.202606241344-02026-07-02redhat
redhatsamba-0:4.19.4-105.el9_4.42026-06-23redhat
redhatsamba-0:4.15.5-16.el8_6.12026-06-23redhat
redhatsamba-0:4.17.5-7.el8_8.12026-06-23redhat
redhatsamba-0:4.21.3-114.el10_0.12026-06-23redhat
redhatsamba-0:4.17.5-105.el9_2.52026-06-23redhat
redhatsamba-0:4.21.3-14.el9_6.12026-06-15redhat
redhatsamba-0:4.23.5-10.el9_82026-06-10redhat
redhatsamba-0:4.19.4-16.el8_102026-06-03redhat
redhatsamba-0:4.23.5-109.el10_22026-06-03redhat

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

(6 across 6 ecosystems)
Alpine:v3.23(1)
PackageVulnerable rangeFixed inDependents
samba—4.22.10-r0—
Alpine:v3.24(1)
PackageVulnerable rangeFixed inDependents
samba—4.23.8-r0—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
samba2:4.13.13+dfsg-1~deb11u1 ... 2:4.13.5+dfsg-2 (8 versions)2:4.13.13+dfsg-1~deb11u8—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
samba2:4.17.10+dfsg-0+deb12u1 ... 2:4.17.9+dfsg-0+deb12u3~bpo11+1 (13 versions)2:4.17.12+dfsg-0+deb12u4—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
samba2:4.22.3+dfsg-4 ... 2:4.22.8+dfsg-0+deb13u1 (7 versions)2:4.22.8+dfsg-0+deb13u2—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
samba2:4.22.3+dfsg-4 ... 2:4.24.3+dfsg-1~bpo13+1 (30 versions)2:4.24.3+dfsg-1—

Weakness Classification(1)

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

Additional Vendor Advisories

(1)

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 18× in last 7d / 94× 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 253 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-2340?
CVE-2026-2340 is a medium vulnerability published on May 27, 2026. A flaw was found in Samba’s vfs_worm module. The module is intended to provide write-once, read-many (WORM) protections by preventing modification of files after a configurable grace period. Due to insufficient validation during rename operations, an authenticated user with write access to a share…
When was CVE-2026-2340 disclosed?
CVE-2026-2340 was first published in the National Vulnerability Database on May 27, 2026, with the most recent update on August 26, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-2340 actively exploited?
CVE-2026-2340 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 41.5% of all scored CVEs.
What is the CVSS score of CVE-2026-2340?
CVE-2026-2340 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2026-2340?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-2340, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-2340

Explore →

Is Your Infrastructure Affected by CVE-2026-2340?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs