Vulnerability-Lookup

PYSEC-2026-2195

Vulnerability from pysec - Published: 2026-02-09 20:15 - Updated: 2026-07-13 05:49

Details

Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. Prior to 2.20.0, CORSConfig.allowed_origins_regex is constructed using a regex built from configured allowlist values and used with fullmatch() for validation. Because metacharacters are not escaped, a malicious origin can match unexpectedly. The check relies on allowed_origins_regex.fullmatch(origin). This vulnerability is fixed in 2.20.0.

Severity

6.5 (Medium)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Impacted products

Name	purl
litestar	pkg:pypi/litestar

Aliases

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {},
      "package": {
        "ecosystem": "PyPI",
        "name": "litestar",
        "purl": "pkg:pypi/litestar"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.20.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.0.0a0",
        "2.0.0",
        "2.0.0a3",
        "2.0.0a4",
        "2.0.0a5",
        "2.0.0a6",
        "2.0.0a7",
        "2.0.0b1",
        "2.0.0b2",
        "2.0.0b3",
        "2.0.0b4",
        "2.0.0rc1",
        "2.0.1",
        "2.1.0",
        "2.1.1",
        "2.10.0",
        "2.11.0",
        "2.12.0",
        "2.12.1",
        "2.13.0",
        "2.14.0",
        "2.15.0",
        "2.15.1",
        "2.15.2",
        "2.16.0",
        "2.17.0",
        "2.18.0",
        "2.19.0",
        "2.2.0",
        "2.2.1",
        "2.3.0",
        "2.3.1",
        "2.3.2",
        "2.4.0",
        "2.4.1",
        "2.4.2",
        "2.4.3",
        "2.4.4",
        "2.4.5",
        "2.5.0",
        "2.5.1",
        "2.5.2",
        "2.5.3",
        "2.5.4",
        "2.5.5",
        "2.6.0",
        "2.6.1",
        "2.6.2",
        "2.6.3",
        "2.6.4",
        "2.7.0",
        "2.7.1",
        "2.7.2",
        "2.8.0",
        "2.8.1",
        "2.8.2",
        "2.8.3",
        "2.9.0",
        "2.9.1"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-25478",
    "GHSA-2p2x-hpg8-cqp2"
  ],
  "details": "Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. Prior to 2.20.0, CORSConfig.allowed_origins_regex is constructed using a regex built from configured allowlist values and used with fullmatch() for validation. Because metacharacters are not escaped, a malicious origin can match unexpectedly. The check relies on allowed_origins_regex.fullmatch(origin). This vulnerability is fixed in 2.20.0.",
  "id": "PYSEC-2026-2195",
  "modified": "2026-07-13T05:49:36.934067Z",
  "published": "2026-02-09T20:15:57.017Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://docs.litestar.dev/2/release-notes/changelog.html#2.20.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/litestar-org/litestar/releases/tag/v2.20.0"
    },
    {
      "type": "FIX",
      "url": "https://github.com/litestar-org/litestar/commit/eb87703b309efcc0d1b087dcb12784e76b003d5a"
    },
    {
      "type": "EVIDENCE",
      "url": "https://github.com/litestar-org/litestar/security/advisories/GHSA-2p2x-hpg8-cqp2"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-25478 (GCVE-0-2026-25478)

Vulnerability from cvelistv5 – Published: 2026-02-09 18:46 – Updated: 2026-02-10 16:01

Title

Litestar has a CORS origin allowlist bypass due to unescaped regex metacharacters in allowed origins

Summary

Severity

7.4 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-942 - Permissive Cross-domain Policy with Untrusted Domains

Assigner

GitHub_M

References

4 references

URL	Tags
https://github.com/litestar-org/litestar/security…	x_refsource_CONFIRM
https://github.com/litestar-org/litestar/commit/e…	x_refsource_MISC
https://docs.litestar.dev/2/release-notes/changel…	x_refsource_MISC
https://github.com/litestar-org/litestar/releases…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
litestar-org	litestar	Affected: < 2.20.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-25478",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-02-10T15:30:25.275815Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-02-10T16:01:16.807Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "litestar",
          "vendor": "litestar-org",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 2.20.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. Prior to 2.20.0, CORSConfig.allowed_origins_regex is constructed using a regex built from configured allowlist values and used with fullmatch() for validation. Because metacharacters are not escaped, a malicious origin can match unexpectedly. The check relies on allowed_origins_regex.fullmatch(origin). This vulnerability is fixed in 2.20.0."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-942",
              "description": "CWE-942: Permissive Cross-domain Policy with Untrusted Domains",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-02-09T18:46:56.445Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/litestar-org/litestar/security/advisories/GHSA-2p2x-hpg8-cqp2",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/litestar-org/litestar/security/advisories/GHSA-2p2x-hpg8-cqp2"
        },
        {
          "name": "https://github.com/litestar-org/litestar/commit/eb87703b309efcc0d1b087dcb12784e76b003d5a",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/litestar-org/litestar/commit/eb87703b309efcc0d1b087dcb12784e76b003d5a"
        },
        {
          "name": "https://docs.litestar.dev/2/release-notes/changelog.html#2.20.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://docs.litestar.dev/2/release-notes/changelog.html#2.20.0"
        },
        {
          "name": "https://github.com/litestar-org/litestar/releases/tag/v2.20.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/litestar-org/litestar/releases/tag/v2.20.0"
        }
      ],
      "source": {
        "advisory": "GHSA-2p2x-hpg8-cqp2",
        "discovery": "UNKNOWN"
      },
      "title": "Litestar has a CORS origin allowlist bypass due to unescaped regex metacharacters in allowed origins"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-25478",
    "datePublished": "2026-02-09T18:46:56.445Z",
    "dateReserved": "2026-02-02T16:31:35.820Z",
    "dateUpdated": "2026-02-10T16:01:16.807Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

GHSA-2P2X-HPG8-CQP2

Vulnerability from github – Published: 2026-02-09 17:18 – Updated: 2026-02-09 22:38

Summary

Litestar's CORS origin allowlist has a bypass due to unescaped regex metacharacters in allowed origins

Details

Summary

CORS origin validation can be bypassed because the allowed-origins allowlist is compiled into a regex without escaping metacharacters (notably .). An allowed origin like https://good.example can match https://goodXexample, resulting in Access-Control-Allow-Origin being set for an untrusted origin

Details

CORSConfig.allowed_origins_regex is constructed using a regex built from configured allowlist values and used with fullmatch() for validation. Because metacharacters are not escaped, a malicious origin can match unexpectedly. The check relies on allowed_origins_regex.fullmatch(origin).

PoC

Server (poc_cors_server.py)

from litestar import Litestar, get
from litestar.config.cors import CORSConfig

@get("/c")
async def c() -> str:
    return "ok"

cors = CORSConfig(
    allow_origins=["https://good.example"],
    allow_credentials=True,
)
app = Litestar([c], cors_config=cors)

uvicorn poc_cors_server:app --host 127.0.0.1 --port 8002

Client (poc_cors_client.py)

import http.client

def req(origin: str) -> tuple[int, str | None]:
    c = http.client.HTTPConnection("127.0.0.1", 8002, timeout=3)
    c.request("GET", "/c", headers={"Origin": origin, "Host": "example.com"})
    r = c.getresponse()
    r.read()
    acao = r.getheader("Access-Control-Allow-Origin")
    c.close()
    return r.status, acao

print("evil:", req("https://evil.example"))
print("bypass:", req("https://goodXexample"))

Expected (vulnerable behavior):

Origin: https://evil.example → no ACAO Origin: https://goodXexample → ACAO: https://goodxexample/ (bypass)

Impact

Type: CORS policy bypass (cross-origin data exposure risk) Who is impacted: apps using CORS allowlists to restrict browser cross-origin reads. If allow_credentials=True and authenticated endpoints return sensitive data, an attacker-controlled site can potentially read responses in a victim’s browser session.

Severity

7.4 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "litestar"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.19.0"
            },
            {
              "fixed": "2.20.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.19.0"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-25478"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-942"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-02-09T17:18:52Z",
    "nvd_published_at": "2026-02-09T20:15:57Z",
    "severity": "HIGH"
  },
  "details": "### Summary\nCORS origin validation can be bypassed because the allowed-origins allowlist is compiled into a regex without escaping metacharacters (notably .). An allowed origin like https://good.example can match https://goodXexample, resulting in Access-Control-Allow-Origin being set for an untrusted origin\n\n### Details\nCORSConfig.allowed_origins_regex is constructed using a regex built from configured allowlist values and used with fullmatch() for validation. Because metacharacters are not escaped, a malicious origin can match unexpectedly. The check relies on allowed_origins_regex.fullmatch(origin).\n\n### PoC\nServer (poc_cors_server.py)\n\n```\nfrom litestar import Litestar, get\nfrom litestar.config.cors import CORSConfig\n\n@get(\"/c\")\nasync def c() -\u003e str:\n    return \"ok\"\n\ncors = CORSConfig(\n    allow_origins=[\"https://good.example\"],\n    allow_credentials=True,\n)\napp = Litestar([c], cors_config=cors)\n```\n\n`uvicorn poc_cors_server:app --host 127.0.0.1 --port 8002`\n\nClient (poc_cors_client.py)\n\n```\nimport http.client\n\ndef req(origin: str) -\u003e tuple[int, str | None]:\n    c = http.client.HTTPConnection(\"127.0.0.1\", 8002, timeout=3)\n    c.request(\"GET\", \"/c\", headers={\"Origin\": origin, \"Host\": \"example.com\"})\n    r = c.getresponse()\n    r.read()\n    acao = r.getheader(\"Access-Control-Allow-Origin\")\n    c.close()\n    return r.status, acao\n\nprint(\"evil:\", req(\"https://evil.example\"))\nprint(\"bypass:\", req(\"https://goodXexample\")) \n```\n\nExpected (vulnerable behavior):\n\nOrigin: https://evil.example \u2192 no ACAO\nOrigin: https://goodXexample \u2192 ACAO: https://goodxexample/ (bypass)\n\n### Impact\nType: CORS policy bypass (cross-origin data exposure risk)\nWho is impacted: apps using CORS allowlists to restrict browser cross-origin reads. If allow_credentials=True and authenticated endpoints return sensitive data, an attacker-controlled site can potentially read responses in a victim\u2019s browser session.",
  "id": "GHSA-2p2x-hpg8-cqp2",
  "modified": "2026-02-09T22:38:05Z",
  "published": "2026-02-09T17:18:52Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/litestar-org/litestar/security/advisories/GHSA-2p2x-hpg8-cqp2"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-25478"
    },
    {
      "type": "WEB",
      "url": "https://github.com/litestar-org/litestar/commit/eb87703b309efcc0d1b087dcb12784e76b003d5a"
    },
    {
      "type": "WEB",
      "url": "https://docs.litestar.dev/2/release-notes/changelog.html#2.20.0"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/litestar-org/litestar"
    },
    {
      "type": "WEB",
      "url": "https://github.com/litestar-org/litestar/releases/tag/v2.20.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Litestar\u0027s CORS origin allowlist has a bypass due to unescaped regex metacharacters in allowed origins"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

PYSEC-2026-2195

CVE-2026-25478 (GCVE-0-2026-25478)

GHSA-2P2X-HPG8-CQP2

Summary

Details

PoC

Impact

Tags

Sightings

Nomenclature