CVE-2026-31537

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-04-24. 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

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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

smb: server: make use of smbdirect_socket.send_io.bcredits

It turns out that our code will corrupt the stream of reassabled data transfer messages when we trigger an immendiate (empty) send.

In order to fix this we'll have a single 'batch' credit per connection. And code getting that credit is free to use as much messages until remaining_length reaches 0, then the batch credit it given back and the next logical send can happen.

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

April 24, 2026

Last Modified

April 28, 2026

Advisory Details (3)

Auto-updated Aug 2, 2026
No patch confirmed yet.
generic

smb: server: make use of smbdirect_socket.send_io.bcredits - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/79242e7b6bc63efec28b7c235bc320806afce6c0
generic

smb: server: make use of smbdirect_socket.send_io.bcredits - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/5ef18a2e66f2f33fdac64437bddfb9fe6389fdc7
generic

smb: server: make use of smbdirect_socket.send_io.bcredits - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/34abd408c8ba24d7c97bd02ba874d8c714f49db1

Vendor Advisories for CVE-2026-31537(1)

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

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
linuxKernel @ 6.18.11—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

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 7.2~rc7-1~exp1 (350 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 7.2~rc7-1~exp1 (174 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 6.18~rc7-1~exp1 (101 versions)6.18.12-1—

Data Freshness Timeline

(refreshed 4× in last 7d / 29× 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 195 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-31537?
CVE-2026-31537 is a medium vulnerability published on April 24, 2026. In the Linux kernel, the following vulnerability has been resolved: smb: server: make use of smbdirectsocket.sendio.bcredits It turns out that our code will corrupt the stream of reassabled data transfer messages when we trigger an immendiate (empty) send. In order to fix this we'll have a single…
When was CVE-2026-31537 disclosed?
CVE-2026-31537 was first published in the National Vulnerability Database on April 24, 2026, with the most recent update on April 28, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-31537 actively exploited?
CVE-2026-31537 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 97.8% of all scored CVEs.
What is the CVSS score of CVE-2026-31537?
CVE-2026-31537 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-31537?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-31537, 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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