CVE-2026-51221

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-06-30. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 3 sources updated this week
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: None knownExposed: 0

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

A buffer overflow in the Get_Attribute_List function of EIPStackGroup OpENer commit 76b95c allows attackers to cause a Denial of Service (DoS) via supplying a crafted Common Packet Format (CPF) packet.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
38(Track)
EG Risk 38/100SSVC: 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
Severity75% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
28%
KEV
Not listed

Published

June 29, 2026

Last Modified

June 30, 2026

Advisory Details (2)

Auto-updated Jun 30, 2026
No patch confirmed yet.
generic

Malformed CPF and Get_Attribute_List request leads to pointer corruption and `denial of service` in OpENer · Issue #567 · EIPStackGroup/OpENer · GitHub

https://github.com/EIPStackGroup/OpENer/issues/567
generic

GitHub - EIPStackGroup/OpENer: OpENer is an EtherNet/IP stack for I/O adapter devices. It supports multiple I/O and explicit connections and includes objects and services for making EtherNet/IP-compliant products as defined in the ODVA specification. · GitHub

https://github.com/EIPStackGroup/OpENer

Vendor Advisories for CVE-2026-51221(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 23× in last 7d / 87× 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.

  1. 2026-07-31 09:08 UTCGHSA enrichment
  2. 2026-07-30 22:14 UTCEG score recompute
  3. 2026-07-30 22:14 UTCGHSA enrichment
  4. 2026-07-30 16:28 UTCEPSS rescore
  5. 2026-07-30 11:09 UTCEG score recompute
  6. 2026-07-30 11:09 UTCGHSA enrichment
  7. 2026-07-30 01:30 UTCEPSS rescore
  8. 2026-07-30 00:08 UTCGHSA enrichment
  9. 2026-07-29 12:22 UTCGHSA enrichment
  10. 2026-07-29 01:27 UTCEG score recompute
  11. 2026-07-29 01:26 UTCGHSA enrichment
  12. 2026-07-28 15:37 UTCEPSS rescore
  13. 2026-07-28 14:31 UTCGHSA enrichment
  14. 2026-07-28 01:02 UTCEG score recompute
  15. 2026-07-28 01:02 UTCGHSA enrichment
  16. 2026-07-27 12:13 UTCGHSA enrichment
  17. 2026-07-27 01:18 UTCEG score recompute
  18. 2026-07-27 01:18 UTCGHSA enrichment
  19. 2026-07-26 14:54 UTCEPSS rescore
  20. 2026-07-26 14:23 UTCEG score recompute
  21. 2026-07-26 14:23 UTCGHSA enrichment
  22. 2026-07-25 14:18 UTCEPSS rescore
  23. 2026-07-24 14:18 UTCEPSS rescore
  24. 2026-07-23 14:18 UTCEPSS rescore
  25. 2026-07-23 03:19 UTCEG score recompute
Show 67 more
  1. 2026-07-22 14:08 UTCEPSS rescore
  2. 2026-07-20 17:08 UTCEPSS rescore
  3. 2026-07-19 14:31 UTCEPSS rescore
  4. 2026-07-19 14:31 UTCEPSS rescore
  5. 2026-07-19 02:29 UTCEPSS rescore
  6. 2026-07-18 10:04 UTCEPSS rescore
  7. 2026-07-16 22:48 UTCGHSA enrichment
  8. 2026-07-16 17:03 UTCEPSS rescore
  9. 2026-07-16 11:54 UTCGHSA enrichment
  10. 2026-07-16 01:00 UTCGHSA enrichment
  11. 2026-07-15 16:57 UTCEPSS rescore
  12. 2026-07-15 16:57 UTCEPSS rescore
  13. 2026-07-15 14:06 UTCGHSA enrichment
  14. 2026-07-15 03:09 UTCGHSA enrichment
  15. 2026-07-15 02:00 UTCEPSS rescore
  16. 2026-07-15 02:00 UTCEPSS rescore
  17. 2026-07-14 16:12 UTCGHSA enrichment
  18. 2026-07-14 05:15 UTCGHSA enrichment
  19. 2026-07-13 22:31 UTCEPSS rescore
  20. 2026-07-13 18:21 UTCGHSA enrichment
  21. 2026-07-13 07:22 UTCGHSA enrichment
  22. 2026-07-13 06:13 UTCEPSS rescore
  23. 2026-07-13 06:13 UTCEPSS rescore
  24. 2026-07-12 20:27 UTCGHSA enrichment
  25. 2026-07-12 09:32 UTCGHSA enrichment
  26. 2026-07-12 05:46 UTCEPSS rescore
  27. 2026-07-11 22:38 UTCGHSA enrichment
  28. 2026-07-11 11:42 UTCGHSA enrichment
  29. 2026-07-11 08:27 UTCEPSS rescore
  30. 2026-07-11 08:27 UTCEPSS rescore
  31. 2026-07-11 00:47 UTCGHSA enrichment
  32. 2026-07-10 13:52 UTCGHSA enrichment
  33. 2026-07-10 02:57 UTCGHSA enrichment
  34. 2026-07-09 19:10 UTCEPSS rescore
  35. 2026-07-09 19:10 UTCEPSS rescore
  36. 2026-07-09 16:02 UTCGHSA enrichment
  37. 2026-07-09 05:06 UTCGHSA enrichment
  38. 2026-07-08 18:11 UTCGHSA enrichment
  39. 2026-07-08 15:16 UTCEPSS rescore
  40. 2026-07-08 15:16 UTCEPSS rescore
  41. 2026-07-08 07:16 UTCGHSA enrichment
  42. 2026-07-07 20:16 UTCGHSA enrichment
  43. 2026-07-07 13:46 UTCEPSS rescore
  44. 2026-07-07 13:46 UTCEPSS rescore
  45. 2026-07-07 09:22 UTCGHSA enrichment
  46. 2026-07-06 22:27 UTCGHSA enrichment
  47. 2026-07-06 16:27 UTCEPSS rescore
  48. 2026-07-06 16:27 UTCEPSS rescore
  49. 2026-07-06 11:32 UTCGHSA enrichment
  50. 2026-07-06 02:23 UTCEPSS rescore
  51. 2026-07-06 00:37 UTCGHSA enrichment
  52. 2026-07-05 13:42 UTCGHSA enrichment
  53. 2026-07-05 02:47 UTCGHSA enrichment
  54. 2026-07-05 02:30 UTCEPSS rescore
  55. 2026-07-04 15:51 UTCGHSA enrichment
  56. 2026-07-04 06:31 UTCEPSS rescore
  57. 2026-07-04 04:56 UTCGHSA enrichment
  58. 2026-07-03 17:56 UTCGHSA enrichment
  59. 2026-07-03 06:58 UTCGHSA enrichment
  60. 2026-07-02 20:00 UTCEG score recompute▲ 7.50
  61. 2026-07-02 20:00 UTCGHSA enrichment
  62. 2026-07-01 15:07 UTCEPSS rescore
  63. 2026-06-30 23:22 UTCEPSS rescore
  64. 2026-06-30 14:32 UTCNVD updateCVSS v3 → 7.5 · severity → HIGH
  65. 2026-06-29 22:18 UTCNVD update
  66. 2026-06-29 21:57 UTCEG score recompute
  67. 2026-06-29 21:57 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-51221?
CVE-2026-51221 is a high vulnerability published on June 29, 2026. A buffer overflow in the GetAttributeList function of EIPStackGroup OpENer commit 76b95c allows attackers to cause a Denial of Service (DoS) via supplying a crafted Common Packet Format (CPF) packet.
When was CVE-2026-51221 disclosed?
CVE-2026-51221 was first published in the National Vulnerability Database on June 29, 2026, with the most recent update on June 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-51221 actively exploited?
CVE-2026-51221 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 72.3% of all scored CVEs.
What is the CVSS score of CVE-2026-51221?
CVE-2026-51221 has a CVSS v3.1 base score of 7.5 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-51221?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-51221, 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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