CVE-2026-38821

HIGHPre-NVD 7.17.1—
EchelonGraph scoreHIGH confidence

Score 7.1 from GitHub Security Advisory (severity: HIGH) published 2026-08-28. a secondary CVSS source baseline 7.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
7.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.1Exploit: None knownExposed: 0

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

A heap-based buffer overflow vulnerability exists in openNDS before 11.0.0 that allows an unauthenticated attacker on the captive portal network to crash the openNDS daemon (denial of service) and potentially achieve remote code execution. This is in http_microhttpd.c.

CVSS v3
7.1
EG Score
7.1(high)
EG Risk
32(Track)
EG Risk 32/100SSVC: 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
Severity71% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
10%
KEV
Not listed

Published

August 28, 2026

Last Modified

September 9, 2026

Advisory Details (1)

Auto-updated Aug 28, 2026
Patch available. Sources: github_commit.
github_commit Patch Available

commit 3b5f7ef40cd0 (openNDS/openNDS)

Patch available: openNDS/openNDS v11.0.0 (contains commit 3b5f7ef40cd0)

https://github.com/openNDS/openNDS/commit/3b5f7ef40cd048826d3c4a16f61a73a1768fd5a9

Vendor Advisories for CVE-2026-38821(1)

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

Affected Packages

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
opennds10.2.0+dfsg-1, 10.3.0+dfsg-0.1, 10.3.1+dfsg-1, 9.10.0-1——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
opennds10.3.1+dfsg-1——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
opennds10.3.1+dfsg-1——

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 28× in last 7d / 101× 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 101 total refreshes for this CVE.

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

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-38821?
CVE-2026-38821 is a high vulnerability published on August 28, 2026. A heap-based buffer overflow vulnerability exists in openNDS before 11.0.0 that allows an unauthenticated attacker on the captive portal network to crash the openNDS daemon (denial of service) and potentially achieve remote code execution. This is in http_microhttpd.c.
When was CVE-2026-38821 disclosed?
CVE-2026-38821 was first published in the National Vulnerability Database on August 28, 2026, with the most recent update on September 9, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-38821 actively exploited?
CVE-2026-38821 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 89.7% of all scored CVEs.
What is the CVSS score of CVE-2026-38821?
CVE-2026-38821 has a CVSS v3 base score of 7.1 (NVD).
How do I remediate CVE-2026-38821?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-38821, 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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