CVE-2026-47774

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.7%, top 51% 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 week
7.5
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 1%CVSS: 7.5Exploit: NoneExposed: 0

A fix is available — apply it.

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.35.11, 1.36.7, 1.37.3, and 1.38.1, a vulnerability in Envoy's HTTP/2 downstream request processing allows an unauthenticated remote client to trigger excessive memory consumption, potentially resulting in OOM termination of the Envoy process and denial of service. The issue arises from the combination of two behaviors. First, cookie header bytes are not fully accounted for during request header size validation in Envoy. Second, HPACK header block limits in oghttp2/quiche are enforced on encoded bytes without a corresponding limit on total decoded header size. Together, these behaviors allow a malicious client to cause large decoded header allocations while bypassing the intended request header size protections. Versions 1.35.11, 1.36.7, 1.37.3, and 1.38.1 contain a fix. No complete workaround is known short of applying a fix. Possible temporary mitigations include disabling downstream HTTP/2 where operationally feasible; enforcing stricter request header and cookie limits before traffic reaches Envoy; and monitoring Envoy memory usage for abnormal growth under HTTP/2 traffic.

CVSS v3
7.5
EG Score
7.5(medium)
EPSS
49.0%
KEV
Not listed

Published

June 17, 2026

Last Modified

July 6, 2026

Advisory Details (2)

Auto-updated Jun 17, 2026
Patch available. Sources: github.
generic

oss-security - Re: HTTP/2 Bomb affects Apache httpd, nginx, envoy, & pingora

http://www.openwall.com/lists/oss-security/2026/06/04/15
github Patch Available

HTTP/2 memory exhaustion via cookie header size bypass and HPACK amplification · Advisory · envoyproxy/envoy · GitHub

https://github.com/envoyproxy/envoy/security/advisories/GHSA-22m2-hvr2-xqc8

Vendor Advisories for CVE-2026-47774(6)

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

Patch Availability(5)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatopenshift-service-mesh/proxyv2-rhel9:17816047242026-06-18redhat
redhatopenshift-service-mesh/istio-proxyv2-rhel9:17810699082026-06-16redhat
redhatopenshift-service-mesh/istio-proxyv2-rhel9:17810701582026-06-16redhat
redhatopenshift-service-mesh/istio-proxyv2-rhel9:17810709672026-06-16redhat
redhatopenshift-service-mesh/istio-proxyv2-rhel9:17810945202026-06-16redhat

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(3)

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

Data Freshness Timeline

(refreshed 32× in last 7d / 97× 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. 2026-07-06 23:35 UTCEG score recompute
  2. 2026-07-06 23:35 UTCVendor advisory
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 10:30 UTCEG score recompute
  5. 2026-07-06 10:30 UTCVendor advisory
  6. 2026-07-06 02:23 UTCEPSS rescore
  7. 2026-07-05 20:40 UTCEG score recompute
  8. 2026-07-05 20:40 UTCVendor advisory
  9. 2026-07-05 07:35 UTCEG score recompute
  10. 2026-07-05 07:35 UTCVendor advisory
  11. 2026-07-05 02:30 UTCEPSS rescore
  12. 2026-07-04 18:25 UTCEG score recompute
  13. 2026-07-04 18:25 UTCVendor advisory
  14. 2026-07-04 06:31 UTCEPSS rescore
  15. 2026-07-04 05:11 UTCEG score recompute
  16. 2026-07-04 05:11 UTCVendor advisory
  17. 2026-07-03 16:01 UTCEG score recompute
  18. 2026-07-03 16:01 UTCVendor advisory
  19. 2026-07-03 02:57 UTCEG score recompute
  20. 2026-07-03 02:57 UTCVendor advisory
  21. 2026-07-02 13:51 UTCEG score recompute
  22. 2026-07-02 13:51 UTCVendor advisory
  23. 2026-07-02 00:47 UTCEG score recompute
  24. 2026-07-02 00:47 UTCVendor advisory
  25. 2026-07-01 15:07 UTCEPSS rescore
Show 72 more
  1. 2026-07-01 11:38 UTCEG score recompute
  2. 2026-07-01 11:38 UTCVendor advisory
  3. 2026-06-30 23:22 UTCEPSS rescore
  4. 2026-06-30 22:34 UTCEG score recompute
  5. 2026-06-30 22:34 UTCVendor advisory
  6. 2026-06-30 09:28 UTCEG score recompute
  7. 2026-06-30 09:28 UTCVendor advisory
  8. 2026-06-29 20:24 UTCEG score recompute
  9. 2026-06-29 20:24 UTCVendor advisory
  10. 2026-06-29 07:20 UTCEG score recompute
  11. 2026-06-29 07:20 UTCVendor advisory
  12. 2026-06-28 18:17 UTCEG score recompute
  13. 2026-06-28 18:17 UTCVendor advisory
  14. 2026-06-28 14:07 UTCEPSS rescore
  15. 2026-06-28 05:12 UTCEG score recompute
  16. 2026-06-28 05:12 UTCVendor advisory
  17. 2026-06-28 04:56 UTCEPSS rescore
  18. 2026-06-28 04:56 UTCEPSS rescore
  19. 2026-06-27 16:09 UTCEG score recompute
  20. 2026-06-27 16:09 UTCVendor advisory
  21. 2026-06-27 03:08 UTCEPSS rescore
  22. 2026-06-27 03:04 UTCEG score recompute
  23. 2026-06-27 03:04 UTCVendor advisory
  24. 2026-06-26 13:58 UTCEG score recompute
  25. 2026-06-26 13:58 UTCVendor advisory
  26. 2026-06-26 00:49 UTCEG score recompute
  27. 2026-06-26 00:49 UTCVendor advisory
  28. 2026-06-25 13:49 UTCEPSS rescore
  29. 2026-06-25 11:44 UTCEG score recompute
  30. 2026-06-25 11:44 UTCVendor advisory
  31. 2026-06-24 22:40 UTCEG score recompute
  32. 2026-06-24 22:40 UTCVendor advisory
  33. 2026-06-24 14:05 UTCEPSS rescore
  34. 2026-06-24 09:36 UTCEG score recompute
  35. 2026-06-24 09:36 UTCVendor advisory
  36. 2026-06-23 21:33 UTCEPSS rescore
  37. 2026-06-23 21:33 UTCEPSS rescore
  38. 2026-06-23 20:26 UTCEG score recompute
  39. 2026-06-23 20:26 UTCVendor advisory
  40. 2026-06-23 07:19 UTCEG score recompute
  41. 2026-06-23 07:19 UTCVendor advisory
  42. 2026-06-22 18:09 UTCEG score recompute
  43. 2026-06-22 18:09 UTCVendor advisory
  44. 2026-06-22 14:25 UTCEPSS rescore
  45. 2026-06-22 14:25 UTCEPSS rescore
  46. 2026-06-22 05:06 UTCEG score recompute
  47. 2026-06-22 05:06 UTCVendor advisory
  48. 2026-06-21 16:02 UTCEG score recompute
  49. 2026-06-21 16:02 UTCVendor advisory
  50. 2026-06-21 14:56 UTCEPSS rescore
  51. 2026-06-21 14:56 UTCEPSS rescore
  52. 2026-06-21 02:33 UTCEG score recompute
  53. 2026-06-21 02:33 UTCVendor advisory
  54. 2026-06-21 01:59 UTCEPSS rescore
  55. 2026-06-21 01:59 UTCEPSS rescore
  56. 2026-06-20 13:26 UTCEG score recompute
  57. 2026-06-20 13:26 UTCVendor advisory
  58. 2026-06-20 00:23 UTCEG score recompute
  59. 2026-06-20 00:23 UTCVendor advisory
  60. 2026-06-19 19:26 UTCEPSS rescore
  61. 2026-06-19 19:26 UTCEPSS rescore
  62. 2026-06-19 11:07 UTCEG score recompute
  63. 2026-06-19 11:07 UTCVendor advisory
  64. 2026-06-18 22:02 UTCEG score recompute
  65. 2026-06-18 22:02 UTCVendor advisory
  66. 2026-06-18 17:52 UTCEPSS rescore
  67. 2026-06-18 17:52 UTCEPSS rescore
  68. 2026-06-18 08:57 UTCEG score recompute
  69. 2026-06-18 08:57 UTCVendor advisory
  70. 2026-06-17 19:51 UTCEG score recompute
  71. 2026-06-17 19:51 UTCVendor advisory
  72. 2026-06-17 19:50 UTCNVD updatefirst tracked

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-47774?
CVE-2026-47774 is a high vulnerability published on June 17, 2026. Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.35.11, 1.36.7, 1.37.3, and 1.38.1, a vulnerability in Envoy's HTTP/2 downstream request processing allows an unauthenticated remote client to trigger excessive memory consumption, potentially…
When was CVE-2026-47774 disclosed?
CVE-2026-47774 was first published in the National Vulnerability Database on June 17, 2026, with the most recent update on July 6, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-47774 actively exploited?
CVE-2026-47774 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 49.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-47774?
CVE-2026-47774 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-47774?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-47774, 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

Explore the affected products and dependency analysis for CVE-2026-47774

Explore →

Is Your Infrastructure Affected by CVE-2026-47774?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs