{"id":"CVE-2020-26244","aliases":["GHSA-4fjv-pmhg-3rfg","PYSEC-2020-69"],"title":"Multiple cryptographic issues in Python oic","summary":"Multiple cryptographic issues in Python oic","severity":"medium","cvss":6.8,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N","vendor":"oic","product":"oic","ecosystem":"pip","affected":["oic < 1.2.1"],"patched":["oic 1.2.1"],"published":"2020-12-04","updated":"2026-07-08","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-4fjv-pmhg-3rfg","references":[{"url":"https://github.com/OpenIDC/pyoidc/security/advisories/GHSA-4fjv-pmhg-3rfg"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-26244"},{"url":"https://github.com/OpenIDC/pyoidc/commit/62f8d753fa17c8b1f29f8be639cf0b33afb02498"},{"url":"https://github.com/OpenIDC/pyoidc"},{"url":"https://github.com/OpenIDC/pyoidc/releases/tag/1.2.1"},{"url":"https://github.com/pypa/advisory-database/tree/main/vulns/oic/PYSEC-2020-69.yaml"},{"url":"https://pypi.org/project/oic"}],"tags":["osv","pip"],"epss":0.00832,"epssPercentile":0.56082,"ingestedAt":"2026-07-08T18:25:45.477Z","slug":"CVE-2020-26244","body":"## Overview\n\n### Impact\n* Client implementations using this library\n\n### Issues\n1) The IdToken signature algorithm was not checked automatically, but only if the expected algorithm was passed in as a kwarg.\n2) JWA `none` algorithm was allowed in all flows.\n3) `oic.consumer.Consumer.parse_authz` returns an unverified IdToken. The verification of the token was left to the discretion of the implementator.\n4) `iat` claim was not checked for sanity (i.e. it could be in the future)\n\n### Patches\n1) IdToken signature is now always checked.\n2) JWA `none` algorithm is now allowed only if using the `response_type` `code`\n3) IdToken verification is now done automatically.\n4) `iat` claim is now checked for sanity.\n\n## Affected packages\n\n- `oic < 1.2.1`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `oic 1.2.1`","depth":"sunlit","depthScore":38,"depthScoreParts":{"impact":37.4,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}