{"id":"CVE-2026-57178","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-57178","generatedAt":"2026-10-28T03:24:34.519Z","title":"Applications using this backend could treat unsigned attacker-controlled data as a verified VK identity.","description":"Python Social Auth is a social authentication/registration mechanism. Prior to version 5.0.0, the `vk-app` backend accepted VK application callback data without verifying the callback signature when the `auth_key` parameter was omitted. Applications using this backend could treat unsigned attacker-controlled data as a verified VK identity. An attacker could choose callback fields such as `viewer_id`, `access_token`, `api_id`, and `api_result`, potentially allowing authentication as an arbitrary VK user ID. The issue affects only applications using the `vk-app` backend. The issue has been fixed in version 5.0.0 by requiring `auth_key` to be present and valid before callback data is trusted.","published":"2026-09-24T18:17:15.000Z","lastModified":"2026-09-28T18:17:24.000Z","status":"Awaiting Analysis","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":7.4,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"},"cwe":["CWE-287","CWE-347"],"affected":[],"epss":{"score":0.0016,"percentile":0.05159,"date":"2026-10-26","history":[{"date":"2026-09-25","score":0.0016,"percentile":0.04471}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.16%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[{"kind":"new","label":"New CVE","at":"2026-09-24T18:17:15.000Z","detail":{"score":"7.4","severity":"HIGH","publishedAt":"2026-09-24T18:17:14.970Z"},"summary":"New CVE, high severity (CVSS 7.4)."}],"references":[{"url":"https://github.com/python-social-auth/social-core/security/advisories/GHSA-3c93-f73f-qc9h","source":"security-advisories@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-57178","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}