CVE-2026-16158

CRITICALNVD 10.010.0—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 10.0 under NVD CVSS v3. EPSS exploit probability: 0.2%, top 86% 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, nvd
10.0EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 10.0Exploit: None knownExposed: 0

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

Impact: @fastify/reply-from versions from 8.3.1 up to but not including 12.6.4 build the internal URL cache key by concatenating the destination and source path without a delimiter. Different destination and source pairs can therefore produce the same key while resolving to different upstream URLs. When getUpstream selects an upstream from request data, a URL cached for one upstream can be reused for a request intended for another upstream, causing cross-upstream data access and modification. The default configuration is affected. Setting disableCache to true prevents the behavior. Patches: upgrade to @fastify/reply-from 12.6.4. Workarounds: pass disableCache: true when registering the plugin.

CVSS v3
10.0
EG Score
10.0(medium)
EG Risk
45(Track)
EG Risk 45/100SSVC: 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
Severity100% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
14%
KEV
Not listed

Published

July 18, 2026

Last Modified

August 5, 2026

Advisory Details (2)

Auto-updated Sep 9, 2026
Patch available. Sources: github.
github Patch Available

@fastify/reply-from vulnerable to cross-upstream request routing via URL cache key collision · Advisory · fastify/fastify-reply-from · GitHub

https://github.com/fastify/fastify-reply-from/security/advisories/GHSA-v574-6498-x57v
generic

Security Advisories | OpenJS Foundation CVE Numbering Authority

https://cna.openjsf.org/security-advisories.html

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 45× 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. 2026-09-11 14:52 UTCEPSS rescore
  2. 2026-09-11 09:36 UTCEPSS rescore
  3. 2026-09-10 09:34 UTCEPSS rescore
  4. 2026-09-08 22:00 UTCEPSS rescore
  5. 2026-09-07 23:59 UTCEG score recompute
  6. 2026-09-07 16:01 UTCEPSS rescore
  7. 2026-09-06 17:36 UTCEG score recompute
  8. 2026-09-06 13:47 UTCEPSS rescore
  9. 2026-09-05 20:25 UTCEG score recompute
  10. 2026-09-02 14:11 UTCEPSS rescore
  11. 2026-09-01 13:53 UTCEPSS rescore
  12. 2026-09-01 04:39 UTCEPSS rescore
  13. 2026-08-30 20:11 UTCEG score recompute
  14. 2026-08-30 19:17 UTCEPSS rescore
  15. 2026-08-30 03:13 UTCEG score recompute
  16. 2026-08-30 01:22 UTCEPSS rescore
  17. 2026-08-28 21:41 UTCEPSS rescore
  18. 2026-08-27 21:25 UTCEG score recompute
  19. 2026-08-27 14:25 UTCEPSS rescore
  20. 2026-08-26 22:33 UTCEG score recompute
  21. 2026-08-26 14:46 UTCEPSS rescore
  22. 2026-08-25 16:21 UTCEG score recompute
  23. 2026-08-25 13:48 UTCEPSS rescore
  24. 2026-08-24 19:13 UTCEG score recompute
  25. 2026-08-24 09:47 UTCEG score recompute
Show 70 more
  1. 2026-08-23 04:12 UTCEG score recompute
  2. 2026-08-23 00:19 UTCEPSS rescore
  3. 2026-08-22 02:50 UTCEG score recompute
  4. 2026-08-21 23:49 UTCEPSS rescore
  5. 2026-08-21 00:54 UTCEG score recompute
  6. 2026-08-20 22:55 UTCEPSS rescore
  7. 2026-08-19 23:24 UTCEG score recompute
  8. 2026-08-19 17:03 UTCEPSS rescore
  9. 2026-08-18 19:53 UTCEG score recompute
  10. 2026-08-18 13:48 UTCEPSS rescore
  11. 2026-08-17 15:02 UTCEG score recompute
  12. 2026-08-17 13:47 UTCEPSS rescore
  13. 2026-08-16 17:49 UTCEG score recompute
  14. 2026-08-16 14:56 UTCEPSS rescore
  15. 2026-08-16 05:05 UTCEG score recompute
  16. 2026-08-16 02:14 UTCEPSS rescore
  17. 2026-08-15 03:47 UTCEG score recompute
  18. 2026-08-15 01:30 UTCEPSS rescore
  19. 2026-08-13 22:10 UTCEG score recompute
  20. 2026-08-13 22:00 UTCEPSS rescore
  21. 2026-08-12 16:31 UTCEG score recompute
  22. 2026-08-12 13:50 UTCEPSS rescore
  23. 2026-08-11 15:11 UTCEG score recompute
  24. 2026-08-11 13:42 UTCEPSS rescore
  25. 2026-08-11 02:31 UTCEG score recompute
  26. 2026-08-11 00:00 UTCEPSS rescore
  27. 2026-08-09 16:39 UTCEG score recompute
  28. 2026-08-09 13:46 UTCEPSS rescore
  29. 2026-08-08 19:34 UTCEG score recompute
  30. 2026-08-08 16:37 UTCEPSS rescore
  31. 2026-08-07 18:15 UTCEG score recompute
  32. 2026-08-06 16:57 UTCEG score recompute
  33. 2026-08-06 13:46 UTCEPSS rescore
  34. 2026-08-05 19:51 UTCEG score recompute▲ 1.30
  35. 2026-08-05 19:51 UTCNVD updateCVSS v3 → 10 · severity → CRITICAL
  36. 2026-08-05 19:17 UTCEPSS rescore
  37. 2026-08-05 01:15 UTCEG score recompute
  38. 2026-08-04 15:10 UTCEPSS rescore
  39. 2026-08-04 13:10 UTCEG score recompute
  40. 2026-08-04 10:38 UTCEPSS rescore
  41. 2026-08-03 13:01 UTCEG score recompute
  42. 2026-08-03 10:35 UTCEPSS rescore
  43. 2026-08-02 12:52 UTCEG score recompute
  44. 2026-08-02 02:26 UTCEPSS rescore
  45. 2026-08-01 12:42 UTCEG score recompute
  46. 2026-08-01 04:15 UTCEPSS rescore
  47. 2026-07-31 00:17 UTCEG score recompute
  48. 2026-07-30 12:13 UTCEG score recompute
  49. 2026-07-30 01:30 UTCEPSS rescore
  50. 2026-07-28 23:58 UTCEG score recompute
  51. 2026-07-27 23:40 UTCEG score recompute
  52. 2026-07-27 14:13 UTCEPSS rescore
  53. 2026-07-26 23:23 UTCEG score recompute
  54. 2026-07-26 14:54 UTCEPSS rescore
  55. 2026-07-26 14:54 UTCEPSS rescore
  56. 2026-07-26 11:17 UTCEG score recompute
  57. 2026-07-25 14:17 UTCEPSS rescore
  58. 2026-07-25 14:17 UTCEPSS rescore
  59. 2026-07-24 14:17 UTCEPSS rescore
  60. 2026-07-23 14:18 UTCEPSS rescore
  61. 2026-07-23 03:05 UTCEG score recompute
  62. 2026-07-23 00:08 UTCEG score recompute
  63. 2026-07-22 14:08 UTCEPSS rescore
  64. 2026-07-21 15:24 UTCEPSS rescore
  65. 2026-07-20 17:53 UTCEG score recompute
  66. 2026-07-20 17:08 UTCEPSS rescore
  67. 2026-07-19 14:30 UTCEPSS rescore
  68. 2026-07-18 14:05 UTCEG score recompute
  69. 2026-07-18 12:40 UTCEG score recompute
  70. 2026-07-18 12:39 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-16158?
CVE-2026-16158 is a critical vulnerability published on July 18, 2026. Impact: @fastify/reply-from versions from 8.3.1 up to but not including 12.6.4 build the internal URL cache key by concatenating the destination and source path without a delimiter. Different destination and source pairs can therefore produce the same key while resolving to different upstream URLs.…
When was CVE-2026-16158 disclosed?
CVE-2026-16158 was first published in the National Vulnerability Database on July 18, 2026, with the most recent update on August 5, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-16158 actively exploited?
CVE-2026-16158 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 86.1% of all scored CVEs.
What is the CVSS score of CVE-2026-16158?
CVE-2026-16158 has a CVSS v3 base score of 10.0 (NVD).
How do I remediate CVE-2026-16158?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-16158, 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.

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