{"dataType": "CVE_RECORD", "dataVersion": "5.1", "cveMetadata": {"cveId": "CVE-2023-40021", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2023-08-08T13:46:25.243Z", "datePublished": "2023-08-16T20:25:22.726Z", "dateUpdated": "2024-08-02T18:24:54.658Z"}, "containers": {"cna": {"title": "Timing Attack Reveals CSRF Tokens in oppia", "problemTypes": [{"descriptions": [{"cweId": "CWE-203", "lang": "en", "description": "CWE-203: Observable Discrepancy", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-208", "lang": "en", "description": "CWE-208: Observable Timing Discrepancy", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/oppia/oppia/security/advisories/GHSA-49jp-pjc3-2532", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/oppia/oppia/security/advisories/GHSA-49jp-pjc3-2532"}, {"name": "https://github.com/oppia/oppia/pull/18769", "tags": ["x_refsource_MISC"], "url": "https://github.com/oppia/oppia/pull/18769"}, {"name": "https://github.com/oppia/oppia/commit/b89bf808378c1236874b5797a7bda32c77b4af23", "tags": ["x_refsource_MISC"], "url": "https://github.com/oppia/oppia/commit/b89bf808378c1236874b5797a7bda32c77b4af23"}, {"name": "https://github.com/oppia/oppia/blob/3a05c3558a292f3db9e658e60e708c266c003fd0/core/controllers/base.py#L964-L990", "tags": ["x_refsource_MISC"], "url": "https://github.com/oppia/oppia/blob/3a05c3558a292f3db9e658e60e708c266c003fd0/core/controllers/base.py#L964-L990"}], "affected": [{"vendor": "oppia", "product": "oppia", "versions": [{"version": ">= 1.1.0, < 3.3.2-hotfix-2", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2023-08-16T20:25:22.726Z"}, "descriptions": [{"lang": "en", "value": "Oppia is an online learning platform. When comparing a received CSRF token against the expected token, Oppia uses the string equality operator (`==`), which is not safe against timing attacks. By repeatedly submitting invalid tokens, an attacker can brute-force the expected CSRF token character by character. Once they have recovered the token, they can then submit a forged request on behalf of a logged-in user and execute privileged actions on that user's behalf. In particular the function to validate received CSRF tokens is at `oppia.core.controllers.base.CsrfTokenManager.is_csrf_token_valid`. An attacker who can lure a logged-in Oppia user to a malicious website can perform any change on Oppia that the user is authorized to do, including changing profile information; creating, deleting, and changing explorations; etc. Note that the attacker cannot change a user's login credentials. An attack would need to complete within 1 second because every second, the time used in computing the token changes. This issue has been addressed in commit `b89bf80837` which has been included in release `3.3.2-hotfix-2`. Users are advised to upgrade. There are no known workarounds for this vulnerability."}], "source": {"advisory": "GHSA-49jp-pjc3-2532", "discovery": "UNKNOWN"}}, "adp": [{"providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-02T18:24:54.658Z"}, "title": "CVE Program Container", "references": [{"name": "https://github.com/oppia/oppia/security/advisories/GHSA-49jp-pjc3-2532", "tags": ["x_refsource_CONFIRM", "x_transferred"], "url": "https://github.com/oppia/oppia/security/advisories/GHSA-49jp-pjc3-2532"}, {"name": "https://github.com/oppia/oppia/pull/18769", "tags": ["x_refsource_MISC", "x_transferred"], "url": "https://github.com/oppia/oppia/pull/18769"}, {"name": "https://github.com/oppia/oppia/commit/b89bf808378c1236874b5797a7bda32c77b4af23", "tags": ["x_refsource_MISC", "x_transferred"], "url": "https://github.com/oppia/oppia/commit/b89bf808378c1236874b5797a7bda32c77b4af23"}, {"name": "https://github.com/oppia/oppia/blob/3a05c3558a292f3db9e658e60e708c266c003fd0/core/controllers/base.py#L964-L990", "tags": ["x_refsource_MISC", "x_transferred"], "url": "https://github.com/oppia/oppia/blob/3a05c3558a292f3db9e658e60e708c266c003fd0/core/controllers/base.py#L964-L990"}]}]}}

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