CVE-2026-21840

LOWPre-NVD 3.13.1—
EchelonGraph scoreHIGH confidence

Score 3.1 from GitHub Security Advisory (severity: LOW) published 2026-07-15. a secondary CVSS source baseline 3.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
3.1
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 3.1Exploit: NoneExposed: 0

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

HCL BigFix Platform is affected by a user enumeration vulnerability which might allow an attacker, through careful system control and response time monitoring, to perform some level of user enumeration for the BigFix service.

CVSS v3
3.1
EG Score
3.1(high)
EG Risk
—
EPSS
4.9%
KEV
Not listed

Published

July 14, 2026

Last Modified

July 15, 2026

References (1)

Vendor Advisories for CVE-2026-21840(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 14× in last 7d / 18× 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. 2026-07-22 14:08 UTCEPSS rescore
  2. 2026-07-21 15:24 UTCEPSS rescore
  3. 2026-07-21 15:24 UTCEPSS rescore
  4. 2026-07-20 17:08 UTCEPSS rescore
  5. 2026-07-19 14:31 UTCEPSS rescore
  6. 2026-07-19 14:31 UTCEPSS rescore
  7. 2026-07-19 02:29 UTCEPSS rescore
  8. 2026-07-19 02:28 UTCEPSS rescore
  9. 2026-07-18 10:04 UTCEPSS rescore
  10. 2026-07-18 10:04 UTCEPSS rescore
  11. 2026-07-17 07:12 UTCEG score recompute
  12. 2026-07-17 07:12 UTCGHSA enrichment
  13. 2026-07-16 17:03 UTCEPSS rescore
  14. 2026-07-16 17:03 UTCEPSS rescore
  15. 2026-07-15 16:57 UTCEPSS rescore
  16. 2026-07-15 16:57 UTCEPSS rescore
  17. 2026-07-14 22:01 UTCEG score recompute
  18. 2026-07-14 22:00 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-21840?
CVE-2026-21840 is a low vulnerability published on July 14, 2026. HCL BigFix Platform is affected by a user enumeration vulnerability which might allow an attacker, through careful system control and response time monitoring, to perform some level of user enumeration for the BigFix service.
When was CVE-2026-21840 disclosed?
CVE-2026-21840 was first published in the National Vulnerability Database on July 14, 2026, with the most recent update on July 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-21840 actively exploited?
CVE-2026-21840 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 4.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-21840?
CVE-2026-21840 has a CVSS v3 base score of 3.1 (NVD).
How do I remediate CVE-2026-21840?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-21840, 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-2026-21840

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