CVE-2026-43929

HIGHNVD 8.28.2—
EchelonGraph scoreMEDIUM confidence

Score 8.2 from GitHub Security Advisory (severity: HIGH) published 2026-05-05. NVD baseline CVSS 8.2; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Elevated
8.2
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 8.2Exploit: NoneExposed: 0

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

ssrfcheck is a library that checks if a string contains a potential SSRF attack. In 1.3.0 and earlier, ssrfcheck fails to block Server-Side Request Forgery attacks when the target private IP address is encoded as an IPv4-mapped IPv6 address (e.g. http://[::ffff:127.0.0.1]/). The WHATWG URL parser built into Node.js silently normalizes the IPv4 notation inside the brackets to compressed hex form ([::ffff:7f00:1]) before the library's private-IP regex ever runs. The regex was written to match dot-notation only and therefore never matches any real input — all seven IANA private IPv4 ranges, including the AWS/GCP/Azure metadata address 169.254.169.254, are bypassed. Any application using isSSRFSafeURL() to guard HTTP requests made with user-supplied URLs is fully exposed to SSRF.

CVSS v3
8.2
EG Score
8.2(medium)
EPSS
13.3%
KEV
Not listed

Published

May 12, 2026

Last Modified

May 13, 2026

Advisory Details (1)

Auto-updated May 12, 2026
🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available

Server-Side Request Forgery (SSRF) and Incomplete List of Disallowed Inputs in ssrfcheck · Advisory · felippe-regazio/ssrfcheck · GitHub

https://github.com/felippe-regazio/ssrfcheck/security/advisories/GHSA-j4rj-2jr5-m439

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
npmssrfcheck—ghsa

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
ssrfcheck———

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 6× in last 7d / 58× 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.

Showing the most recent 100 of 141 total refreshes for this CVE.

  1. 2026-07-11 08:27 UTCEPSS rescore
  2. 2026-07-09 19:10 UTCEPSS rescore
  3. 2026-07-08 15:16 UTCEPSS rescore
  4. 2026-07-07 13:46 UTCEPSS rescore
  5. 2026-07-06 16:27 UTCEPSS rescore
  6. 2026-07-06 02:23 UTCEPSS rescore
  7. 2026-07-05 02:30 UTCEPSS rescore
  8. 2026-07-04 06:31 UTCEPSS rescore
  9. 2026-07-01 15:07 UTCEPSS rescore
  10. 2026-06-30 23:22 UTCEPSS rescore
  11. 2026-06-29 14:06 UTCEPSS rescore
  12. 2026-06-28 14:07 UTCEPSS rescore
  13. 2026-06-28 12:59 UTCEG score recompute
  14. 2026-06-28 12:59 UTCGHSA enrichment
  15. 2026-06-28 04:56 UTCEPSS rescore
  16. 2026-06-28 01:27 UTCEG score recompute
  17. 2026-06-28 01:27 UTCGHSA enrichment
  18. 2026-06-27 08:20 UTCEG score recompute
  19. 2026-06-27 08:20 UTCGHSA enrichment
  20. 2026-06-27 03:08 UTCEPSS rescore
  21. 2026-06-26 20:44 UTCEG score recompute
  22. 2026-06-26 20:44 UTCGHSA enrichment
  23. 2026-06-25 21:11 UTCEG score recompute
  24. 2026-06-25 21:11 UTCGHSA enrichment
  25. 2026-06-25 13:49 UTCEPSS rescore
Show 75 more
  1. 2026-06-25 13:49 UTCEPSS rescore
  2. 2026-06-24 14:05 UTCEPSS rescore
  3. 2026-06-23 21:33 UTCEPSS rescore
  4. 2026-06-22 14:25 UTCEPSS rescore
  5. 2026-06-22 14:25 UTCEPSS rescore
  6. 2026-06-21 14:56 UTCEPSS rescore
  7. 2026-06-21 14:56 UTCEPSS rescore
  8. 2026-06-21 01:59 UTCEPSS rescore
  9. 2026-06-19 19:25 UTCEPSS rescore
  10. 2026-06-18 17:52 UTCEPSS rescore
  11. 2026-06-18 17:52 UTCEPSS rescore
  12. 2026-06-17 21:53 UTCEG score recompute
  13. 2026-06-17 21:53 UTCGHSA enrichment
  14. 2026-06-17 17:53 UTCEPSS rescore
  15. 2026-06-16 23:34 UTCEG score recompute
  16. 2026-06-16 23:34 UTCGHSA enrichment
  17. 2026-06-16 17:52 UTCEPSS rescore
  18. 2026-06-16 05:19 UTCEG score recompute
  19. 2026-06-16 05:19 UTCGHSA enrichment
  20. 2026-06-15 17:49 UTCEPSS rescore
  21. 2026-06-14 22:41 UTCEG score recompute
  22. 2026-06-14 22:41 UTCGHSA enrichment
  23. 2026-06-14 11:32 UTCEG score recompute
  24. 2026-06-14 11:32 UTCGHSA enrichment
  25. 2026-06-14 00:23 UTCEG score recompute
  26. 2026-06-14 00:23 UTCGHSA enrichment
  27. 2026-06-13 23:00 UTCEPSS rescore
  28. 2026-06-13 00:36 UTCEG score recompute
  29. 2026-06-13 00:36 UTCGHSA enrichment
  30. 2026-06-12 23:12 UTCEPSS rescore
  31. 2026-06-12 23:12 UTCEPSS rescore
  32. 2026-06-12 13:26 UTCEG score recompute
  33. 2026-06-12 13:26 UTCGHSA enrichment
  34. 2026-06-12 02:14 UTCEG score recompute
  35. 2026-06-12 02:14 UTCGHSA enrichment
  36. 2026-06-11 15:05 UTCEG score recompute
  37. 2026-06-11 15:05 UTCGHSA enrichment
  38. 2026-06-11 14:00 UTCEPSS rescore
  39. 2026-06-11 03:55 UTCEG score recompute
  40. 2026-06-11 03:55 UTCGHSA enrichment
  41. 2026-06-10 22:18 UTCEPSS rescore
  42. 2026-06-10 16:46 UTCEG score recompute
  43. 2026-06-10 16:46 UTCGHSA enrichment
  44. 2026-06-10 13:22 UTCEPSS rescore
  45. 2026-06-10 13:22 UTCEPSS rescore
  46. 2026-06-10 05:37 UTCEG score recompute
  47. 2026-06-10 05:37 UTCGHSA enrichment
  48. 2026-06-09 18:28 UTCEG score recompute
  49. 2026-06-09 18:28 UTCGHSA enrichment
  50. 2026-06-09 07:19 UTCEG score recompute
  51. 2026-06-09 07:19 UTCGHSA enrichment
  52. 2026-06-08 20:09 UTCEG score recompute
  53. 2026-06-08 20:09 UTCGHSA enrichment
  54. 2026-06-08 14:17 UTCEPSS rescore
  55. 2026-06-08 14:17 UTCEPSS rescore
  56. 2026-06-08 06:21 UTCEG score recompute
  57. 2026-06-08 06:21 UTCGHSA enrichment
  58. 2026-06-07 19:12 UTCEG score recompute
  59. 2026-06-07 19:12 UTCGHSA enrichment
  60. 2026-06-07 15:25 UTCEPSS rescore
  61. 2026-06-07 15:25 UTCEPSS rescore
  62. 2026-06-07 08:03 UTCEG score recompute
  63. 2026-06-07 08:03 UTCGHSA enrichment
  64. 2026-06-06 20:54 UTCEG score recompute
  65. 2026-06-06 20:54 UTCGHSA enrichment
  66. 2026-06-06 13:47 UTCEPSS rescore
  67. 2026-06-06 13:47 UTCEPSS rescore
  68. 2026-06-06 09:45 UTCEG score recompute
  69. 2026-06-06 09:44 UTCGHSA enrichment
  70. 2026-06-05 22:47 UTCEPSS rescore
  71. 2026-06-05 22:35 UTCEG score recompute
  72. 2026-06-05 22:35 UTCGHSA enrichment
  73. 2026-06-05 11:26 UTCEG score recompute
  74. 2026-06-05 11:26 UTCGHSA enrichment
  75. 2026-06-05 06:10 UTCEPSS rescore

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-43929?
CVE-2026-43929 is a high vulnerability published on May 12, 2026. ssrfcheck is a library that checks if a string contains a potential SSRF attack. In 1.3.0 and earlier, ssrfcheck fails to block Server-Side Request Forgery attacks when the target private IP address is encoded as an IPv4-mapped IPv6 address (e.g. http://[::ffff:127.0.0.1]/). The WHATWG URL parser…
When was CVE-2026-43929 disclosed?
CVE-2026-43929 was first published in the National Vulnerability Database on May 12, 2026, with the most recent update on May 13, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-43929 actively exploited?
CVE-2026-43929 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 13.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-43929?
CVE-2026-43929 has a CVSS v3 base score of 8.2 (NVD).
How do I remediate CVE-2026-43929?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-43929, 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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