CVE-2026-93567

validatedZero produced an exploit or a check.

GHSA-45h4-vhwh-fmhg ↗EUVD-2026-82943 ↗

check availableZero validated a working check for it.not proven exploitableZero has a detection check, but hasn't produced a full working exploit yet.
cve.orgpublic pocExploit code has been published by someone. Source signals can also carry a PoC (Proof of Concept).kevAttacks confirmed in the real world.
maven:io.netty:netty-codec-http2 >= 4.1.0.Final, <= 4.1.137.Final; >= 4.2.0.Final, <= 4.2.17.Final
fixed in 4.1.138.Final, 4.2.18.Final
CWE-20 Improper Input Validation
ETK-2026-193, permanent identifier
pkg:maven/io.netty/netty-codec-http2
+13dTTV
19mAI analysisAnalysis: how long the AI spent reversing this signal.
Check if you are vulnerable
timeline
0 = cve.org publication
trigger signal (cve.org) +0dcheck available+13dagent stopped
0
+5d
+10d

description

Netty's netty-codec-http2 can map an HTTP/1 CONNECT request to the wrong HTTP/2 tunnel authority during protocol conversion. A remote client may bypass destination-based tunnel or egress controls when an HTTP/1-to-HTTP/2 proxy or gateway accepts CONNECT requests and authorizes the original request target.

mitigation

Upgrade io.netty:netty-codec-http2 to 4.1.138.Final or 4.2.18.Final, as appropriate. Until then, block CONNECT requests that cross an HTTP/1-to-HTTP/2 conversion boundary.

fixed in 4.1.138.Final, 4.2.18.Final

check
available
exploit
no
automationDeterministic: a check that runs on its own, the same request on every target. Contextual: an agentic technique that needs to be applied per target, for bugs that depend on contextual flows.
contextual
auth requiredWhether an attacker needs an account first, based on the CVSS vector's Privileges Required.
no
EPSSEstimate of the chance this CVE is exploited in the next 30 days. Refreshed daily.
2.6%84th percentile
agent run time
19m
cve.org record, t = 0The moment cve.org publishes the CVE in full.
2026-09-18 14:23Z
Δ to public pocExploit code has been published by someone. Source signals can also carry a PoC (Proof of Concept).
–
Δ to kevAttacks confirmed in the real world.
–

outcome

Contextual check: a technique exists and was validated, but no deterministic check could cover this one.

source signals

Public signals that triggered or updated the pipeline. These are inputs for the deltas above.

  1. 2026-09-18 14:23Z
  2. 2026-09-18 14:23Z

this entry in the feed

GET /api/v1/feed/CVE-2026-93567

{
  "etk_id": "ETK-2026-193",
  "cve_id": "CVE-2026-93567",
  "display_id": "CVE-2026-93567",
  "ghsa_id": "GHSA-45h4-vhwh-fmhg",
  "euvd_id": "EUVD-2026-82943",
  "status": "published",
  "anchor_state": "anchored",
  "title": "CONNECT authority confusion in Netty HTTP/2 codec",
  "summary": "Netty's netty-codec-http2 can map an HTTP/1 CONNECT request to the wrong HTTP/2 tunnel authority during protocol conversion. A remote client may bypass destination-based tunnel or egress controls when an HTTP/1-to-HTTP/2 proxy or gateway accepts CONNECT requests and authorizes the original request target.",
  "mitigation": "Upgrade io.netty:netty-codec-http2 to 4.1.138.Final or 4.2.18.Final, as appropriate. Until then, block CONNECT requests that cross an HTTP/1-to-HTTP/2 conversion boundary.",
  "vendor": "maven",
  "product": "maven:io.netty:netty-codec-http2",
  "affected": [
    {
      "affected_notes": [],
      "affected_ranges": [
        ">= 4.1.0.Final, <= 4.1.137.Final"
      ],
      "ecosystem": "maven",
      "fixed_versions": [
        "4.1.138.Final"
      ],
      "package_name": "io.netty:netty-codec-http2",
      "purl": "pkg:maven/io.netty/netty-codec-http2"
    },
    {
      "affected_notes": [],
      "affected_ranges": [
        ">= 4.2.0.Final, <= 4.2.17.Final"
      ],
      "ecosystem": "maven",
      "fixed_versions": [
        "4.2.18.Final"
      ],
      "package_name": "io.netty:netty-codec-http2",
      "purl": "pkg:maven/io.netty/netty-codec-http2"
    }
  ],
  "cwes": [
    20
  ],
  "cvss_score": 7.5,
  "cvss_src": "cna_vendor",
  "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
  "epss_score": 0.0256,
  "epss_percentile": 0.8488,
  "epss_asof": "2026-10-20",
  "automation": "contextual",
  "check": true,
  "check_confidence_basis": "assessed",
  "exploit": false,
  "pipeline_minutes": 18.672742533333334,
  "t0_at": "2026-09-18T14:23:27.219000+00:00",
  "signals": {
    "check": {
      "at": "2026-10-01T02:43:54.095719+00:00",
      "days": 12.514199962025463,
      "is_lower_bound": false,
      "measured_at": "2026-09-18T14:23:27.219000+00:00",
      "url": null
    },
    "trigger_signal": {
      "at": "2026-09-18T14:23:27.219000+00:00",
      "days": 0,
      "is_lower_bound": false,
      "measured_at": "2026-09-18T14:23:27.219000+00:00",
      "url": "https://github.com/netty/netty/security/advisories/GHSA-45h4-vhwh-fmhg"
    }
  }
}

published 2026-10-01 02:25Z
last change 2026-10-21 04:45Z

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