React Router is a router for React. In versions 7.0.0 through 7.17.0, the manifest endpoint could be accessed via unauthenticated targeted requests that would put heavy load on the server and slow down response times. This issue is a follow up to CVE-2026-42342, and does not does not impact React Router applications using Declarative Mode () or Data Mode (createBrowserRouter/). This issue has been fixed in version 7.18.0.
CVE-2026-55685
This high-severity CVE scores 8.7 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). 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).
- High severity, but no confirmed exploitation yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 8.7
- EG Score
- 8.7(low)
- EG Risk
- 44(Track)EG Risk 44/100SSVC: 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 computedSeverity87% × 45%Exploitation0% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- —
- EPSS %ILE
- —
- KEV
- Not listed
Published
July 24, 2026
Last Modified
July 27, 2026
Advisory Details (6)
Auto-updated Jul 27, 2026v7.18.0
Patch available: remix-run/react-router [email protected]
https://github.com/remix-run/react-router/releases/tag/[email protected]react-router/CHANGELOG.md at main · remix-run/react-router · GitHub
https://github.com/remix-run/react-router/blob/main/CHANGELOG.md#v7180commit 09e6020d1950 (remix-run/react-router)
Patch available: remix-run/react-router [email protected] (contains commit 09e6020d1950)
https://github.com/remix-run/react-router/commit/09e6020d1950e54f361f7ad00938ecd4dde60929Optimize route matching internals
Patch available: remix-run/react-router [email protected] (PR #15186 merged 2026-06-15)
https://github.com/remix-run/react-router/pull/15186DoS via unbounded path expansion in __manifest endpoint · Advisory · remix-run/react-router · GitHub
https://github.com/remix-run/react-router/security/advisories/GHSA-8x6r-g9mw-2r78Unauthenticated Denial of Service in React Router __manifest endpoint · Advisory · remix-run/react-router · GitHub
https://github.com/remix-run/react-router/security/advisories/GHSA-chx6-hx7r-mcp5Vendor Advisories for CVE-2026-55685(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 5× in last 7d / 5× 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.
- 2026-07-27 22:25 UTCEG score recompute
- 2026-07-27 21:50 UTCEG score recompute▲ 8.70
- 2026-07-27 21:49 UTCMITRE cvelistV5CVSS v3 → 8.7 · CVSS v4 → 8.7
- 2026-07-27 17:23 UTCEG score recompute
- 2026-07-24 14:12 UTCEG score recompute
Related CVEs(same CWE)
Same CWE
10 shownCWE-400
Frequently asked(4)
What is CVE-2026-55685?
When was CVE-2026-55685 disclosed?
What is the CVSS score of CVE-2026-55685?
How do I remediate CVE-2026-55685?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-55685
Is Your Infrastructure Affected by CVE-2026-55685?
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