CVE-2025-61686

CRITICALPre-NVD 9.19.1—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 16.1%, top 3% 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 weekElevated
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 16%CVSS: 9.1Exploit: Elevated riskExposed: 0

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

React Router is a router for React. In @react-router/node versions 7.0.0 through 7.9.3, @remix-run/deno prior to version 2.17.2, and @remix-run/node prior to version 2.17.2, if createFileSessionStorage() is being used from @react-router/node (or @remix-run/node/@remix-run/deno in Remix v2) with an unsigned cookie, it is possible for an attacker to cause the session to try to read/write from a location outside the specified session file directory. The success of the attack would depend on the permissions of the web server process to access those files. Read files cannot be returned directly to the attacker. Session file reads would only succeed if the file matched the expected session file format. If the file matched the session file format, the data would be populated into the server side session but not directly returned to the attacker unless the application logic returned specific session information. This issue has been patched in @react-router/node version 7.9.4, @remix-run/deno version 2.17.2, and @remix-run/node version 2.17.2.

CVSS v3
9.1
EG Score
9.1(medium)
EG Risk
72(Track)
EG Risk 72/100SSVC: 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
Severity91% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
16%
EPSS %ILE
97%
KEV
Not listed

Published

January 10, 2026

Last Modified

July 15, 2026

Advisory Details (1)

Auto-updated Jun 27, 2026
Patch available. Sources: github.
github Patch Available

Unauthorized file access when using `createFileSessionStorage()` with unsigned cookies · Advisory · remix-run/react-router · GitHub

https://github.com/remix-run/react-router/security/advisories/GHSA-9583-h5hc-x8cw

Affected Packages

(3 across 1 ecosystem)
npm(3)
PackageVulnerable rangeFixed inDependents
@react-router/node—7.9.4—
@remix-run/deno—2.17.2—
@remix-run/node—2.17.2—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 12× in last 7d / 43× 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. 2026-07-27 14:12 UTCEPSS rescore
  2. 2026-07-26 14:54 UTCEPSS rescore
  3. 2026-07-26 14:54 UTCEPSS rescore
  4. 2026-07-25 14:17 UTCEPSS rescore
  5. 2026-07-24 14:17 UTCEPSS rescore
  6. 2026-07-24 14:17 UTCEPSS rescore
  7. 2026-07-23 14:18 UTCEPSS rescore
  8. 2026-07-23 14:18 UTCEPSS rescore
  9. 2026-07-23 10:49 UTCOSV refresh
  10. 2026-07-23 03:00 UTCEG score recompute
  11. 2026-07-22 14:08 UTCEPSS rescore
  12. 2026-07-21 15:24 UTCEPSS rescore
  13. 2026-07-20 17:08 UTCEPSS rescore
  14. 2026-07-19 14:30 UTCEPSS rescore
  15. 2026-07-19 14:30 UTCEPSS rescore
  16. 2026-07-19 02:28 UTCEPSS rescore
  17. 2026-07-18 10:04 UTCEPSS rescore
  18. 2026-07-18 10:04 UTCEPSS rescore
  19. 2026-07-16 17:02 UTCEPSS rescore
  20. 2026-07-15 16:57 UTCEPSS rescore
  21. 2026-07-15 16:57 UTCEPSS rescore
  22. 2026-07-13 22:29 UTCEPSS rescore
  23. 2026-07-12 05:46 UTCEPSS rescore
  24. 2026-07-11 08:27 UTCEPSS rescore
  25. 2026-07-09 19:09 UTCEPSS rescore
Show 67 more
  1. 2026-07-08 15:15 UTCEPSS rescore
  2. 2026-07-07 13:46 UTCEPSS rescore
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 16:27 UTCEPSS rescore
  5. 2026-07-06 06:02 UTCOSV refresh
  6. 2026-07-05 02:30 UTCEPSS rescore
  7. 2026-07-05 02:30 UTCEPSS rescore
  8. 2026-07-04 06:31 UTCEPSS rescore
  9. 2026-07-04 06:30 UTCEPSS rescore
  10. 2026-07-01 15:06 UTCEPSS rescore
  11. 2026-07-01 15:06 UTCEPSS rescore
  12. 2026-06-30 23:22 UTCEPSS rescore
  13. 2026-06-29 14:06 UTCEPSS rescore
  14. 2026-06-29 14:06 UTCEPSS rescore
  15. 2026-06-28 14:07 UTCEPSS rescore
  16. 2026-06-28 14:07 UTCEPSS rescore
  17. 2026-06-28 04:56 UTCEPSS rescore
  18. 2026-06-28 04:55 UTCEPSS rescore
  19. 2026-06-27 03:08 UTCEPSS rescore
  20. 2026-06-25 13:49 UTCEPSS rescore
  21. 2026-06-24 14:04 UTCEPSS rescore
  22. 2026-06-24 14:04 UTCEPSS rescore
  23. 2026-06-23 21:32 UTCEPSS rescore
  24. 2026-06-23 21:32 UTCEPSS rescore
  25. 2026-06-22 14:25 UTCEPSS rescore
  26. 2026-06-21 01:59 UTCEPSS rescore
  27. 2026-06-21 01:59 UTCEPSS rescore
  28. 2026-06-19 19:25 UTCEPSS rescore
  29. 2026-06-19 19:25 UTCEPSS rescore
  30. 2026-06-18 17:52 UTCEPSS rescore
  31. 2026-06-18 17:52 UTCEPSS rescore
  32. 2026-06-17 17:52 UTCEPSS rescore
  33. 2026-06-17 17:35 UTCOSV refresh
  34. 2026-06-16 17:52 UTCEPSS rescore
  35. 2026-06-15 17:48 UTCEPSS rescore
  36. 2026-06-15 17:48 UTCEPSS rescore
  37. 2026-06-14 23:18 UTCEPSS rescore
  38. 2026-06-13 23:00 UTCEPSS rescore
  39. 2026-06-13 23:00 UTCEPSS rescore
  40. 2026-06-12 23:11 UTCEPSS rescore
  41. 2026-06-11 14:00 UTCEPSS rescore
  42. 2026-06-10 22:18 UTCEPSS rescore
  43. 2026-06-10 22:18 UTCEPSS rescore
  44. 2026-06-10 13:22 UTCEPSS rescore
  45. 2026-06-08 14:17 UTCEPSS rescore
  46. 2026-06-08 14:16 UTCEPSS rescore
  47. 2026-06-07 15:24 UTCEPSS rescore
  48. 2026-06-07 15:24 UTCEPSS rescore
  49. 2026-06-06 13:47 UTCEPSS rescore
  50. 2026-06-06 13:47 UTCEPSS rescore
  51. 2026-06-05 22:46 UTCEPSS rescore
  52. 2026-06-05 22:46 UTCEPSS rescore
  53. 2026-06-05 06:10 UTCEPSS rescore
  54. 2026-06-05 06:10 UTCEPSS rescore
  55. 2026-06-04 13:12 UTCEPSS rescore
  56. 2026-06-04 13:12 UTCEPSS rescore
  57. 2026-06-02 20:13 UTCEPSS rescore
  58. 2026-06-02 20:12 UTCEPSS rescore
  59. 2026-06-01 13:51 UTCEPSS rescore
  60. 2026-06-01 13:51 UTCEPSS rescore
  61. 2026-05-31 22:30 UTCEPSS rescore
  62. 2026-05-31 22:30 UTCEPSS rescore
  63. 2026-05-31 00:16 UTCEPSS rescore
  64. 2026-05-31 00:16 UTCEPSS rescore
  65. 2026-05-29 16:20 UTCEG score recompute
  66. 2026-05-29 15:57 UTCOSV refresh
  67. 2026-05-29 13:44 UTCEPSS rescore

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2025-61686?
CVE-2025-61686 is a critical vulnerability published on January 10, 2026. React Router is a router for React. In @react-router/node versions 7.0.0 through 7.9.3, @remix-run/deno prior to version 2.17.2, and @remix-run/node prior to version 2.17.2, if createFileSessionStorage() is being used from @react-router/node (or @remix-run/node/@remix-run/deno in Remix v2) with an…
When was CVE-2025-61686 disclosed?
CVE-2025-61686 was first published in the National Vulnerability Database on January 10, 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-2025-61686 actively exploited?
CVE-2025-61686 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 16% probability of exploitation in the next 30 days, which ranks it in the top 3.5% of all scored CVEs.
What is the CVSS score of CVE-2025-61686?
CVE-2025-61686 has a CVSS v3 base score of 9.1 (NVD).
How do I remediate CVE-2025-61686?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2025-61686, 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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