GHSA-F5WC-C3C7-36MC

Vulnerability from github – Published: 2026-06-25 22:14 – Updated: 2026-08-11 15:31
VLAI
Summary
golang.org/x/crypto doesn't drop invoking agent constraints when forwarding keys
Details

When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of the key on the remote host. The client now serializes all constraint extensions. Additionally, the in-memory keyring returned by NewKeyring() now rejects keys with unsupported constraint extensions instead of silently ignoring them.

Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "golang.org/x/crypto"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.52.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-39832"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-281",
      "CWE-502"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-25T22:14:00Z",
    "nvd_published_at": "2026-05-22T04:16:22Z",
    "severity": "CRITICAL"
  },
  "details": "When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of the key on the remote host. The client now serializes all constraint extensions. Additionally, the in-memory keyring returned by NewKeyring() now rejects keys with unsupported constraint extensions instead of silently ignoring them.",
  "id": "GHSA-f5wc-c3c7-36mc",
  "modified": "2026-08-11T15:31:42Z",
  "published": "2026-06-25T22:14:00Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-39832"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:35833"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:41036"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:41066"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:42146"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:42796"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:43052"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:43692"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:49944"
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    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:52857"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:52910"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-39832"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2480685"
    },
    {
      "type": "PACKAGE",
      "url": "https://cs.opensource.google/go/x/crypto"
    },
    {
      "type": "WEB",
      "url": "https://go.dev/cl/778642"
    },
    {
      "type": "WEB",
      "url": "https://go.dev/issue/79435"
    },
    {
      "type": "WEB",
      "url": "https://groups.google.com/g/golang-announce/c/a082jnz-LvI"
    },
    {
      "type": "WEB",
      "url": "https://pkg.go.dev/vuln/GO-2026-5006"
    },
    {
      "type": "WEB",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-39832.json"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:36199"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:36319"
    },
    {
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      "url": "https://access.redhat.com/errata/RHSA-2026:36625"
    },
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      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:36648"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:36651"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:36796"
    },
    {
      "type": "WEB",
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    },
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      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:37072"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:37123"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:37271"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:37387"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:37410"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:40118"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:40262"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:40945"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:40972"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:41019"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:41031"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "golang.org/x/crypto doesn\u0027t drop invoking agent constraints when forwarding keys"
}



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