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GHSA-MWH4-6H8G-PG8W

Vulnerability from github – Published: 2026-04-01 21:48 – Updated: 2026-04-01 21:48
VLAI
Summary
AIOHTTP has HTTP response splitting via \r in reason phrase
Details

Summary

An attacker who controls the reason parameter when creating a Response may be able to inject extra headers or similar exploits.

Impact

In the unlikely situation that an application allows untrusted data to be used in the response's reason parameter, then an attacker could manipulate the response to send something different from what the developer intended.

Patch: https://github.com/aio-libs/aiohttp/commit/53b35a2f8869c37a133e60bf1a82a1c01642ba2b

Severity
2.7 (Low)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 3.13.3"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "aiohttp"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.13.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-34519"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-113"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-01T21:48:24Z",
    "nvd_published_at": "2026-04-01T21:17:00Z",
    "severity": "LOW"
  },
  "details": "### Summary\n\nAn attacker who controls the `reason` parameter when creating a `Response` may be able to inject extra headers or similar exploits.\n\n### Impact\n\nIn the unlikely situation that an application allows untrusted data to be used in the response\u0027s `reason` parameter, then an attacker could manipulate the response to send something different from what the developer intended.\n\n-----\n\nPatch: https://github.com/aio-libs/aiohttp/commit/53b35a2f8869c37a133e60bf1a82a1c01642ba2b",
  "id": "GHSA-mwh4-6h8g-pg8w",
  "modified": "2026-04-01T21:48:24Z",
  "published": "2026-04-01T21:48:24Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/aio-libs/aiohttp/security/advisories/GHSA-mwh4-6h8g-pg8w"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34519"
    },
    {
      "type": "WEB",
      "url": "https://github.com/aio-libs/aiohttp/commit/53b35a2f8869c37a133e60bf1a82a1c01642ba2b"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/aio-libs/aiohttp"
    },
    {
      "type": "WEB",
      "url": "https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U",
      "type": "CVSS_V4"
    }
  ],
  "summary": "AIOHTTP has HTTP response splitting via \\r in reason phrase"
}



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