CVE-2026-47221

HIGHNVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 0.3%, top 74% 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
Trending — 3 sources updated this week
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: None knownExposed: 0

A fix is available — apply it.

Envoy is an open source edge and service proxy designed for cloud-native applications. From 1.18.0 until 1.35.13, 1.36.9, 1.37.5, and 1.38.3, the router filter contains a null pointer dereference vulnerability when handling HTTP 303 (See Other) internal redirects for body-less non-GET/HEAD requests. When a POST, PUT, DELETE, or PATCH request without a body is sent to a route configured with internal redirect policy that includes 303 in redirect_response_codes, and the upstream responds with HTTP 303, the redirect handling code attempts to drain a request body buffer that was never allocated. This results in a segmentation fault that crashes the entire Envoy process. When route configured with internal_redirect_policy including 303 in redirect_response_codes and upstream must return HTTP 303 response, an unauthenticated attacker can exploit this to cause complete denial of service, terminating all active connections. This vulnerability is fixed in 1.35.13, 1.36.9, 1.37.5, and 1.38.3.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
38(Track)
EG Risk 38/100SSVC: 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
Severity75% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
26%
KEV
Not listed

Published

June 26, 2026

Last Modified

June 27, 2026

Advisory Details (1)

Auto-updated Jun 26, 2026
🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available

Null pointer deref in internal redirects · Advisory · envoyproxy/envoy · GitHub

https://github.com/envoyproxy/envoy/security/advisories/GHSA-rcff-gw58-pjpr

Vendor Advisories for CVE-2026-47221(5)

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

Patch Availability(4)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatopenshift-service-mesh/istio-proxyv2-rhel9:17849535562026-08-03redhat
redhatopenshift-service-mesh/istio-proxyv2-rhel9:17849086392026-08-03redhat
redhatopenshift-service-mesh/istio-proxyv2-rhel9:17849086822026-08-03redhat
redhatopenshift-service-mesh/istio-proxyv2-rhel9:17849537432026-08-03redhat

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.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 24× in last 7d / 84× 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 114 total refreshes for this CVE.

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

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Frequently asked(5)

What is CVE-2026-47221?
CVE-2026-47221 is a high vulnerability published on June 26, 2026. Envoy is an open source edge and service proxy designed for cloud-native applications. From 1.18.0 until 1.35.13, 1.36.9, 1.37.5, and 1.38.3, the router filter contains a null pointer dereference vulnerability when handling HTTP 303 (See Other) internal redirects for body-less non-GET/HEAD…
When was CVE-2026-47221 disclosed?
CVE-2026-47221 was first published in the National Vulnerability Database on June 26, 2026, with the most recent update on June 27, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-47221 actively exploited?
CVE-2026-47221 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 74.3% of all scored CVEs.
What is the CVSS score of CVE-2026-47221?
CVE-2026-47221 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-47221?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-47221, 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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