CVE-2026-21718

CRITICALNVD 9.810.0▲
EchelonGraph scoreMEDIUM confidence

Score 10.0 from GitHub Security Advisory (severity: CRITICAL) published 2026-02-27. NVD baseline CVSS 9.8; sources differ by 0.2.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
10.0EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.8Exploit: None knownExposed: 0

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

An authentication bypass vulnerability exists in Copeland XWEB Pro version 1.12.1 and prior, enabling any attackers to bypass the authentication requirement and achieve pre-authenticated code execution on the system.

CVSS v3
9.8
EG Score
10.0(medium)
EG Risk
50(Track)
EG Risk 50/100SSVC: 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
Severity100% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
37%
KEV
Not listed

Published

February 27, 2026

Last Modified

June 17, 2026

Advisory Details (3)

Auto-updated Sep 14, 2026
Patch available. Sources: cisa.
cisa Patch Available

Copeland XWEB and XWEB Pro | CISA

https://www.cisa.gov/news-events/ics-advisories/icsa-26-057-10
generic

Copeland Controls

https://webapps.copeland.com/Dixell/Pages/SystemSoftwareUpdate
generic

CSAF/csaf_files/OT/white/2026/icsa-26-057-10.json at develop · cisagov/CSAF · GitHub

https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-057-10.json

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 4× in last 7d / 23× 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. 2026-09-18 19:27 UTCEPSS rescore
  2. 2026-09-16 14:07 UTCEPSS rescore
  3. 2026-09-16 05:15 UTCEPSS rescore
  4. 2026-09-13 16:47 UTCEPSS rescore
  5. 2026-09-12 15:01 UTCEPSS rescore
  6. 2026-09-11 14:52 UTCEPSS rescore
  7. 2026-09-10 09:34 UTCEPSS rescore
  8. 2026-09-08 22:00 UTCEPSS rescore
  9. 2026-09-07 16:01 UTCEPSS rescore
  10. 2026-09-06 13:47 UTCEPSS rescore
  11. 2026-09-06 13:47 UTCEPSS rescore
  12. 2026-09-04 05:06 UTCEPSS rescore
  13. 2026-09-02 14:11 UTCEPSS rescore
  14. 2026-09-01 13:53 UTCEPSS rescore
  15. 2026-09-01 04:39 UTCEPSS rescore
  16. 2026-08-30 19:17 UTCEPSS rescore
  17. 2026-08-30 01:22 UTCEPSS rescore
  18. 2026-08-28 21:41 UTCEPSS rescore
  19. 2026-08-27 14:25 UTCEPSS rescore
  20. 2026-08-26 14:46 UTCEPSS rescore
  21. 2026-08-25 13:48 UTCEPSS rescore
  22. 2026-08-23 00:19 UTCEPSS rescore
  23. 2026-08-21 23:49 UTCEPSS rescore
  24. 2026-08-20 22:55 UTCEPSS rescore
  25. 2026-08-19 17:03 UTCEPSS rescore
Show 56 more
  1. 2026-08-18 13:48 UTCEPSS rescore
  2. 2026-08-17 13:47 UTCEPSS rescore
  3. 2026-08-16 14:56 UTCEPSS rescore
  4. 2026-08-16 02:14 UTCEPSS rescore
  5. 2026-08-15 01:30 UTCEPSS rescore
  6. 2026-08-15 01:02 UTCGHSA enrichment
  7. 2026-08-14 21:08 UTCGHSA enrichment
  8. 2026-08-14 12:45 UTCGHSA enrichment
  9. 2026-08-14 08:52 UTCEG score recompute
  10. 2026-08-14 08:52 UTCGHSA enrichment
  11. 2026-08-13 22:00 UTCEPSS rescore
  12. 2026-08-13 04:44 UTCGHSA enrichment
  13. 2026-08-13 00:50 UTCEG score recompute
  14. 2026-08-13 00:50 UTCGHSA enrichment
  15. 2026-08-12 13:50 UTCEPSS rescore
  16. 2026-08-11 23:38 UTCEG score recompute
  17. 2026-08-11 23:38 UTCGHSA enrichment
  18. 2026-08-11 13:42 UTCEPSS rescore
  19. 2026-08-11 06:13 UTCEG score recompute
  20. 2026-08-11 06:13 UTCGHSA enrichment
  21. 2026-08-11 00:00 UTCEPSS rescore
  22. 2026-08-10 13:12 UTCGHSA enrichment
  23. 2026-08-10 08:32 UTCGHSA enrichment
  24. 2026-08-10 01:28 UTCGHSA enrichment
  25. 2026-08-09 21:34 UTCGHSA enrichment
  26. 2026-08-09 17:41 UTCGHSA enrichment
  27. 2026-08-09 13:47 UTCEG score recompute
  28. 2026-08-09 13:47 UTCGHSA enrichment
  29. 2026-08-09 13:46 UTCEPSS rescore
  30. 2026-08-09 08:30 UTCEG score recompute
  31. 2026-08-09 08:30 UTCGHSA enrichment
  32. 2026-08-08 16:37 UTCEPSS rescore
  33. 2026-08-08 08:13 UTCGHSA enrichment
  34. 2026-08-08 04:19 UTCGHSA enrichment
  35. 2026-08-08 00:26 UTCGHSA enrichment
  36. 2026-08-07 20:32 UTCEG score recompute
  37. 2026-08-07 20:32 UTCGHSA enrichment
  38. 2026-08-06 13:46 UTCEPSS rescore
  39. 2026-08-06 06:49 UTCGHSA enrichment
  40. 2026-08-06 02:55 UTCEG score recompute
  41. 2026-08-06 02:55 UTCGHSA enrichment
  42. 2026-08-05 19:17 UTCEPSS rescore
  43. 2026-08-04 15:10 UTCEPSS rescore
  44. 2026-08-04 10:38 UTCEPSS rescore
  45. 2026-08-04 04:55 UTCEG score recompute
  46. 2026-08-04 04:55 UTCGHSA enrichment
  47. 2026-08-03 10:35 UTCEPSS rescore
  48. 2026-08-02 23:18 UTCGHSA enrichment
  49. 2026-08-02 19:25 UTCEG score recompute
  50. 2026-08-02 19:25 UTCGHSA enrichment
  51. 2026-08-02 02:26 UTCEPSS rescore
  52. 2026-08-01 04:15 UTCEPSS rescore
  53. 2026-07-30 01:30 UTCEPSS rescore
  54. 2026-07-27 14:13 UTCEPSS rescore
  55. 2026-07-27 13:35 UTCEG score recompute
  56. 2026-07-27 13:35 UTCGHSA enrichment

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-21718?
CVE-2026-21718 is a critical vulnerability published on February 27, 2026. An authentication bypass vulnerability exists in Copeland XWEB Pro version 1.12.1 and prior, enabling any attackers to bypass the authentication requirement and achieve pre-authenticated code execution on the system.
When was CVE-2026-21718 disclosed?
CVE-2026-21718 was first published in the National Vulnerability Database on February 27, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-21718 actively exploited?
CVE-2026-21718 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 63.3% of all scored CVEs.
What is the CVSS score of CVE-2026-21718?
CVE-2026-21718 has a CVSS v3 base score of 9.8 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 10.0.
How do I remediate CVE-2026-21718?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-21718, 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

Explore the affected products and dependency analysis for CVE-2026-21718

Explore →

Is Your Infrastructure Affected by CVE-2026-21718?

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

Start Free Scan →Browse All CVEs