{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-23996",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-01-19T18:49:20.658Z",
        "datePublished": "2026-01-21T22:29:24.107Z",
        "dateUpdated": "2026-01-22T16:49:16.733Z"
    },
    "containers": {
        "cna": {
            "title": "FastAPI Api Key has a timing side-channel in verify_key that allows statistical key validity detection",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-208",
                            "lang": "en",
                            "description": "CWE-208: Observable Timing Discrepancy",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "HIGH",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "NONE",
                        "baseScore": 3.7,
                        "baseSeverity": "LOW",
                        "confidentialityImpact": "LOW",
                        "integrityImpact": "NONE",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/Athroniaeth/fastapi-api-key/security/advisories/GHSA-95c6-p277-p87g",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/Athroniaeth/fastapi-api-key/security/advisories/GHSA-95c6-p277-p87g"
                },
                {
                    "name": "https://github.com/Athroniaeth/fastapi-api-key/commit/310b2c5c77305f38c63c0b917539a0344071dfd8",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/Athroniaeth/fastapi-api-key/commit/310b2c5c77305f38c63c0b917539a0344071dfd8"
                },
                {
                    "name": "https://github.com/Athroniaeth/fastapi-api-key/releases/tag/1.1.0",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/Athroniaeth/fastapi-api-key/releases/tag/1.1.0"
                }
            ],
            "affected": [
                {
                    "vendor": "Athroniaeth",
                    "product": "fastapi-api-key",
                    "versions": [
                        {
                            "version": "< 1.1.0",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-01-21T22:29:24.107Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "FastAPI Api Key provides a backend-agnostic library that provides an API key system. Version 1.1.0 has a timing side-channel vulnerability in verify_key(). The method applied a random delay only on verification failures, allowing an attacker to statistically distinguish valid from invalid API keys by measuring response latencies. With enough repeated requests, an adversary could infer whether a key_id corresponds to a valid key, potentially accelerating brute-force or enumeration attacks. All users relying on verify_key() for API key authentication prior to the fix are affected. Users should upgrade to version 1.1.0 to receive a patch. The patch applies a uniform random delay (min_delay to max_delay) to all responses regardless of outcome, eliminating the timing correlation. Some workarounds are available. Add an application-level fixed delay or random jitter to all authentication responses (success and failure) before the fix is applied and/or use rate limiting to reduce the feasibility of statistical timing attacks."
                }
            ],
            "source": {
                "advisory": "GHSA-95c6-p277-p87g",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-01-22T15:09:24.050000Z",
                                "id": "CVE-2026-23996",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-01-22T16:49:16.733Z"
                }
            }
        ]
    }
}