CVE-2026-59895

MEDIUMPre-NVD 6.16.1
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 91% 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
6.1
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 6.1Exploit: NoneExposed: 0

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

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.0.0 before 4.12.27, cx() in hono/css composes class names from plain strings but marks the result as already escaped without HTML-escaping the input, allowing untrusted className values used in a JSX class attribute during server-side rendering to break out of the attribute and inject arbitrary markup. This issue is fixed in version 4.12.27.

CVSS v3
6.1
EG Score
6.1(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
Severity61% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS
8.6%
KEV
Not listed

Published

July 8, 2026

Last Modified

July 10, 2026

Advisory Details (3)

Auto-updated Jul 8, 2026
Patch available. Sources: github_commit, github_release, github.
github Patch Available

Server-Side XSS via JSX Escaping Bypass in cx() Utility · Advisory · honojs/hono · GitHub

https://github.com/honojs/hono/security/advisories/GHSA-w62v-xxxg-mg59
github_release Patch Available

v4.12.27

Patch available: honojs/hono v4.12.27

https://github.com/honojs/hono/releases/tag/v4.12.27
github_commit Patch Available

commit cd3f6f7194f0 (honojs/hono)

Patch available: honojs/hono v4.12.27 (contains commit cd3f6f7194f0)

https://github.com/honojs/hono/commit/cd3f6f7194f0e5c9d4b26ae0cf232018d0f388fc

Vendor Advisories for CVE-2026-59895(1)

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

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
hono4.12.27

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 10× in last 7d / 24× 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. 2026-07-23 03:21 UTCEG score recompute
  2. 2026-07-22 14:08 UTCEPSS rescore
  3. 2026-07-22 14:08 UTCEPSS rescore
  4. 2026-07-21 15:25 UTCEPSS rescore
  5. 2026-07-21 15:25 UTCEPSS rescore
  6. 2026-07-20 17:08 UTCEPSS rescore
  7. 2026-07-19 14:31 UTCEPSS rescore
  8. 2026-07-19 02:29 UTCEPSS rescore
  9. 2026-07-18 10:04 UTCEPSS rescore
  10. 2026-07-16 17:03 UTCEPSS rescore
  11. 2026-07-15 16:57 UTCEPSS rescore
  12. 2026-07-15 16:57 UTCEPSS rescore
  13. 2026-07-15 02:00 UTCEPSS rescore
  14. 2026-07-15 02:00 UTCEPSS rescore
  15. 2026-07-13 22:31 UTCEPSS rescore
  16. 2026-07-13 06:13 UTCEPSS rescore
  17. 2026-07-13 06:13 UTCEPSS rescore
  18. 2026-07-12 05:46 UTCEPSS rescore
  19. 2026-07-11 08:27 UTCEPSS rescore
  20. 2026-07-11 08:27 UTCEPSS rescore
  21. 2026-07-09 19:10 UTCEPSS rescore
  22. 2026-07-09 19:10 UTCEPSS rescore
  23. 2026-07-08 16:25 UTCEG score recompute
  24. 2026-07-08 16:24 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-59895?
CVE-2026-59895 is a medium vulnerability published on July 8, 2026. Hono is a Web application framework that provides support for any JavaScript runtime. From 4.0.0 before 4.12.27, cx() in hono/css composes class names from plain strings but marks the result as already escaped without HTML-escaping the input, allowing untrusted className values used in a JSX class…
When was CVE-2026-59895 disclosed?
CVE-2026-59895 was first published in the National Vulnerability Database on July 8, 2026, with the most recent update on July 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-59895 actively exploited?
CVE-2026-59895 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 8.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-59895?
CVE-2026-59895 has a CVSS v3 base score of 6.1 (NVD).
How do I remediate CVE-2026-59895?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-59895, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-59895

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Is Your Infrastructure Affected by CVE-2026-59895?

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