CVE-2026-67424: Flyto2 Core Guarded HTTP Modules Follow Redirects Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-c9hr-64h3-gxpc",
  "modified" : "2026-07-30T14:48:17Z",
  "published" : "2026-07-30T14:48:16Z",
  "aliases" : [ "CVE-2026-67424" ],
  "summary" : "Flyto2 Core: Guarded HTTP modules follow redirects into internal space without per-hop SSRF revalidation",
  "details" : "## Summary\nThe HTTP modules that DO call the SSRF guard (`http.get`, `http.request`, `http.batch`) validate only the initial URL, then issue the request with aiohttp's default `allow_redirects=True` and perform no per-hop revalidation. An attacker hosts a public URL that 302-redirects to an internal address; the guard passes on the public host and aiohttp transparently follows the redirect into internal space, returning the internal body.\n\n## Root Cause\n`src/core/modules/atomic/http/get.py:116` calls `session.get(url, ...)` with no `allow_redirects` argument → aiohttp default `True`. `request.py:60` sets `allow_redirects=follow_redirects` (default True at :327); `batch.py:57` likewise. A repo grep of `http/` for `on_request_redirect` / `response.history` returns NONE — there is no redirect interception or Location revalidation.\n\n## Impact\nFull readable SSRF that defeats the primary SSRF control on the very modules that correctly validate. Confidentiality of internal/metadata responses (C:H), S:C.\n\n## Proof of Concept\nVerified live: `http.get` with allowlisted base `127.0.0.1` followed a `302 Location: http://127.0.0.2/...` (non-allowlisted) and returned `INTERNAL-VIA-REDIRECT`.\n```\nattacker hosts http://attacker.tld/r  ->  302 Location: http://<cloud-metadata-ip>/latest/meta-data/...\nexecute_module http.get {\"url\":\"http://attacker.tld/r\"}\n```\n\n## Attack Chain\n1. Entry: `execute_module http.get {url:\"http://attacker.tld/r\"}` (attacker 302->internal). Guard: `validate_url_with_env_config(url)` (get.py:104). Bypass proof: validation runs on `attacker.tld` (public) → passes; never re-run on the redirect target.\n2. Sink: `session.get(url)` (get.py:116) — no `allow_redirects` arg → aiohttp default True. Bypass proof: grep of `http/` for `on_request_redirect`/`response.history` → NONE.\n3. Impact: aiohttp follows 302 to the internal host; internal body returned (get.py:118).\n\n## Bypass Evidence\nLive PoC followed a 302 into non-allowlisted loopback and returned the internal marker string. aiohttp `ClientSession.get` default `allow_redirects=True`; module never sets it False; no per-hop revalidation exists.\n\n## Affected Versions\n`<= 2.26.6` — `get.py:116`, `request.py:60`, `batch.py:57` present on latest release tag.\n\n## Suggested Fix\nSet `allow_redirects=False` and manually revalidate each `Location` header through `validate_url_with_env_config` before following, or cap and re-check every hop.\n\n## Credit\n\nVulnerability discovered by zx (Jace).",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "flyto-core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.26.7"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 2.26.6"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/flytohub/flyto-core/security/advisories/GHSA-c9hr-64h3-gxpc"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-67424"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/flytohub/flyto-core/commit/0a0a528520ec18f5a21f1ddf858a71cc1edfb6e9"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/flytohub/flyto-core"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/flytohub/flyto-core/releases/tag/v2.26.7"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-918" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-30T14:48:16Z",
    "nvd_published_at" : "2026-07-29T19:16:51Z"
  }
}