{"id":"CVE-2026-33123","summary":"pypdf has inefficient decoding of array-based streams","details":"pypdf is a free and open-source pure-python PDF library. Versions prior to 6.9.1 allow an attacker to craft a malicious PDF which leads to long runtimes and/or large memory usage. Exploitation requires accessing an array-based stream with many entries. This issue has been fixed in version 6.9.1.","aliases":["GHSA-qpxp-75px-xjcp","PYSEC-2026-3023"],"modified":"2026-08-27T14:10:51.932611410Z","published":"2026-03-20T09:09:12.831Z","related":["CGA-23v6-4x7h-5824","openSUSE-SU-2026:10402-1","openSUSE-SU-2026:10403-1"],"database_specific":{"cwe_ids":["CWE-400","CWE-407"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33123.json","cna_assigner":"GitHub_M"},"references":[{"type":"WEB","url":"https://github.com/py-pdf/pypdf/releases/tag/6.9.1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33123.json"},{"type":"ADVISORY","url":"https://github.com/py-pdf/pypdf/security/advisories/GHSA-qpxp-75px-xjcp"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33123"},{"type":"FIX","url":"https://github.com/py-pdf/pypdf/pull/3686"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/py-pdf/pypdf","events":[{"introduced":"0"},{"fixed":"0e5157c2d9440c3594de43ffe27745eb474a2fb9"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"6.9.1"}],"source":["AFFECTED_FIELD","CPE_RANGE","REFERENCES"],"cpe":"cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:*"}}],"versions":["6.9.0","6.8.0","6.7.5","6.7.4","6.7.3","6.7.2","6.7.1","6.7.0","6.6.2","6.6.1","6.6.0","6.5.0","6.4.2","6.4.1","6.4.0","6.3.0","6.2.0","6.1.3","6.1.2","6.1.1","6.1.0","6.0.0","5.9.0","5.8.0","5.7.0","5.6.1","5.6.0","5.5.0","5.4.0","5.3.1","5.3.0","5.2.0","5.1.0","5.0.1","5.0.0","4.3.1","4.3.0","4.2.0","4.1.0","4.0.2","4.0.1","4.0.0","3.17.4","3.17.3","3.17.2","3.17.1","3.17.0","3.16.4","3.16.3","3.16.2","3.16.1","3.16.0","3.15.5","3.15.4","3.15.3","3.15.2","3.15.1","3.15.0","3.14.0","3.13.0","3.12.2","3.12.1","3.12.0","3.11.1","3.11.0","3.10.0","3.9.1","3.9.0","3.8.1","3.8.0","3.7.1","3.7.0","3.6.0","3.5.2","3.5.1","3.5.0","3.4.1","3.4.0","3.3.0","3.2.1","3.2.0","3.0.0","3.1.0","2.12.1","2.12.0","2.11.2","2.11.1","2.11.0","2.10.9","2.10.8","2.10.7","2.10.6","2.10.5","2.10.4","2.10.3","2.10.2","2.10.1","2.10.0","2.9.0","2.8.1","2.8.0","2.7.0","2.6.0","2.5.0","2.4.2","2.4.1","2.4.0","2.3.1","2.3.0","2.2.1","2.2.0","2.1.1","2.1.0","2.0.0","1.28.2","1.28.1","1.28.0","1.27.12","1.27.11","1.27.10","1.27.9","1.27.8","1.27.7","1.27.6","1.27.5","1.27.4","1.27.3","1.27.2","1.27.1","1.27.0","v1.24","1.26.0","v1.25.1","v1.25","v1.23","v1.22","v1.21","v1.20","v1.19","v1.18","v1.17"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-33123.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N"}]}