CVE-2026-81905

MEDIUMPre-NVD 6.36.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 84% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 3 sources updated this week
6.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.3Exploit: None knownExposed: 0

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

Concrete CMS below 9.5.3 stores user validation hashes for multiple purposes (email/registration validation, password reset, and persistent login) in a single table with a type column, but the redemption path resolves a hash by value alone and does not verify its type. As a result, a hash issued for one purpose can be redeemed for another: a long-lived registration hash (60-day expiry) can be submitted to the password-change endpoint to set a new password on the target account, and a password-reset hash can be submitted to the email-validation endpoint to activate an account. Exploitation requires the attacker to first obtain a valid hash through a separate channel (for example email interception, log exposure, or SSRF against an internal mail relay), so the flaw amplifies the impact of any hash disclosure rather than creating a standalone entry point. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting.

CVSS v3
6.3
EG Score
6.3(medium)
EG Risk
28(Track)
EG Risk 28/100SSVC: 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
Severity63% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
16%
KEV
Not listed

Published

September 10, 2026

Last Modified

September 11, 2026

References (1)

Vendor Advisories for CVE-2026-81905(1)

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

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 16× 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.

  1. 2026-09-18 23:38 UTCEG score recompute
  2. 2026-09-18 23:38 UTCGHSA enrichment
  3. 2026-09-18 19:28 UTCEPSS rescore
  4. 2026-09-17 22:28 UTCEG score recompute
  5. 2026-09-17 22:28 UTCGHSA enrichment
  6. 2026-09-16 21:19 UTCEG score recompute
  7. 2026-09-16 21:19 UTCGHSA enrichment
  8. 2026-09-16 14:08 UTCEPSS rescore
  9. 2026-09-16 05:15 UTCEPSS rescore
  10. 2026-09-15 20:09 UTCEG score recompute
  11. 2026-09-15 20:09 UTCGHSA enrichment
  12. 2026-09-15 03:12 UTCEPSS rescore
  13. 2026-09-15 03:12 UTCEPSS rescore
  14. 2026-09-14 18:59 UTCGHSA enrichment
  15. 2026-09-13 17:49 UTCEG score recompute
  16. 2026-09-13 17:49 UTCGHSA enrichment
  17. 2026-09-12 16:39 UTCEG score recompute
  18. 2026-09-12 16:39 UTCGHSA enrichment
  19. 2026-09-11 15:29 UTCEG score recompute
  20. 2026-09-11 15:29 UTCGHSA enrichment
  21. 2026-09-11 14:53 UTCEPSS rescore
  22. 2026-09-11 14:53 UTCEPSS rescore
  23. 2026-09-11 14:53 UTCEG score recompute
  24. 2026-09-11 14:53 UTCGHSA enrichment
  25. 2026-09-11 14:44 UTCEG score recompute
Show 4 more
  1. 2026-09-11 14:44 UTCGHSA enrichment
  2. 2026-09-11 00:25 UTCEG score recompute
  3. 2026-09-10 23:25 UTCEG score recompute
  4. 2026-09-10 23:24 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-81905?
CVE-2026-81905 is a medium vulnerability published on September 10, 2026. Concrete CMS below 9.5.3 stores user validation hashes for multiple purposes (email/registration validation, password reset, and persistent login) in a single table with a type column, but the redemption path resolves a hash by value alone and does not verify its type. As a result, a hash issued…
When was CVE-2026-81905 disclosed?
CVE-2026-81905 was first published in the National Vulnerability Database on September 10, 2026, with the most recent update on September 11, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-81905 actively exploited?
CVE-2026-81905 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 84.1% of all scored CVEs.
What is the CVSS score of CVE-2026-81905?
CVE-2026-81905 has a CVSS v3 base score of 6.3 (NVD).
How do I remediate CVE-2026-81905?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-81905, 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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