{"id":"CVE-2023-46250","aliases":["EUVD-2023-2830","GHSA-wjcc-cq79-p63f","PYSEC-2026-1834","UBUNTU-CVE-2023-46250"],"status":"published","title":"pypdf possible Infinite Loop when PdfWriter(clone_from) is used with a PDF","description":"pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions 3.7.0 through 3.16.4 can craft a PDF which leads to an infinite loop. This infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage. That is, for example, the case when the pypdf-user manipulates an incoming malicious PDF e.g. by merging it with another PDF or by adding annotations. The issue was fixed in version 3.17.0. As a workaround, apply the patch manually by modifying `pypdf/generic/_data_structures.py`.","severity":{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00254,"percentile":0.17139,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-835"],"published":"2023-10-31T15:23:32Z","modified":"2026-11-04T02:46:10Z","fixes":[{"ecosystem":"PyPI","package":"pypdf","fixed_in":["3.17.0"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"pypdf","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.7.0"},{"fixed":"3.17.0"}]}]},{"source":"osv","ecosystem":"PyPI","package":"pypdf","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.7.0"},{"fixed":"3.17.0"}]}],"versions":["3.10.0","3.11.0","3.11.1","3.12.0","3.12.1","3.12.2","3.13.0","3.14.0","3.15.0","3.15.1","3.15.2","3.15.3","3.15.4","3.15.5","3.16.0","3.16.1","3.16.2","3.16.3","3.16.4","3.7.0","3.7.1","3.8.0","3.8.1","3.9.0","3.9.1"]},{"source":"osv","ecosystem":"PyPI","package":"pypdf","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.7.0"},{"fixed":"3.17.0"}]}],"versions":["3.10.0","3.11.0","3.11.1","3.12.0","3.12.1","3.12.2","3.13.0","3.14.0","3.15.0","3.15.1","3.15.2","3.15.3","3.15.4","3.15.5","3.16.0","3.16.1","3.16.2","3.16.3","3.16.4","3.7.0","3.7.1","3.8.0","3.8.1","3.9.0","3.9.1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:16.04:LTS","package":"pypdf2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.23+git20141008-1","1.25.1-1","1.25.1-1ubuntu0.1~esm1","1.25.1-1ubuntu0.1~esm2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"pypdf2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.26.0-2","1.26.0-2ubuntu0.1~esm1","1.26.0-2ubuntu0.1~esm2"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"pypdf2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.26.0-2","1.26.0-3ubuntu1","1.26.0-3ubuntu1.20.04.1","1.26.0-3ubuntu1.20.04.2"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"pypdf2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.26.0-4","1.26.0-4ubuntu0.22.04.1","1.26.0-4ubuntu0.22.04.2"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"pypdf","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.4.1-1","3.17.4-1","4.0.0-1","4.0.1-1","4.0.2-1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"pypdf2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.12.1-3","2.12.1-4"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"pypdf","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.3.1-1","5.4.0-1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"pypdf","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.9.2-1","6.9.2-2"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"pypdf","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.4.0-1","6.9.2-1"]}],"products":[{"vendor":"py-pdf","product":"pypdf"}],"references":[{"url":"https://github.com/py-pdf/pypdf/security/advisories/GHSA-wjcc-cq79-p63f","tags":["x_refsource_CONFIRM","x_transferred","Vendor Advisory","advisory","web","report"]},{"url":"https://github.com/py-pdf/pypdf/pull/2264","tags":["x_refsource_MISC","x_transferred","Issue Tracking","Patch","fix","web","report"]},{"url":"https://github.com/py-pdf/pypdf/commit/9b23ac3c9619492570011d551d521690de9a3e2d","tags":["x_refsource_MISC","x_transferred","Patch","fix","web","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-46250","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-wjcc-cq79-p63f","tags":["advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/46xxx/CVE-2023-46250.json","tags":["advisory"]},{"url":"https://github.com/py-pdf/pypdf","tags":["package"]},{"url":"https://pypi.org/project/pypdf","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2023-46250","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2023-46250","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2023-46250","title":"pypdf possible Infinite Loop when PdfWriter(clone_from) is used with a PDF","description":"pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions 3.7.0 through 3.16.4 can craft a PDF which leads to an infinite loop. This infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage. That is, for example, the case when the pypdf-user manipulates an incoming malicious PDF e.g. by merging it with another PDF or by adding annotations. The issue was fixed in version 3.17.0. As a workaround, apply the patch manually by modifying `pypdf/generic/_data_structures.py`.","status":"published","published":"2023-10-31T15:23:32.852Z","modified":"2024-09-05T18:54:52.306Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-835"],"updated_at":"2026-11-02T14:35:23.309349Z"}],"euvd":[{"id":"EUVD-2023-2830","description":"pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions 3.7.0 through 3.16.4 can craft a PDF which leads to an infinite loop. This infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage. That is, for example, the case when the pypdf-user manipulates an incoming malicious PDF e.g. by merging it with another PDF or by adding annotations. The issue was fixed in version 3.17.0. As a workaround, apply the patch manually by modifying `pypdf/generic/_data_structures.py`.","status":"published","published":"2023-10-31T15:23:32Z","modified":"2024-09-05T18:54:52Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-03T00:56:02.678796Z"}],"ghsa":[{"id":"GHSA-wjcc-cq79-p63f","title":"Possible Infinite Loop when PdfWriter(clone_from) is used with a PDF","description":"### Impact\nAn attacker who uses this vulnerability can craft a PDF which leads to an infinite loop.\nThis infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage.\n\nThat is, for example, the case when the pypdf-user manipulates an incoming malicious PDF e.g. by merging it with another PDF or by adding annotations.\n\n### Patches\nThe issue was fixed with #2264\n\n### Workarounds\nIf you cannot update your version of pypdf, you should modify `pypdf/generic/_data_structures.py` just like #2264 did.","status":"published","published":"2023-10-31T22:22:50Z","modified":"2024-01-08T16:12:18Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-835"],"updated_at":"2026-11-02T14:37:30.183224Z"}],"nvd":[{"id":"CVE-2023-46250","description":"pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions 3.7.0 through 3.16.4 can craft a PDF which leads to an infinite loop. This infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage. That is, for example, the case when the pypdf-user manipulates an incoming malicious PDF e.g. by merging it with another PDF or by adding annotations. The issue was fixed in version 3.17.0. As a workaround, apply the patch manually by modifying `pypdf/generic/_data_structures.py`.","status":"published","published":"2023-10-31T16:15:09.93Z","modified":"2026-11-02T16:06:04.477Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"secondary"},{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary"}],"cwes":["CWE-835"],"updated_at":"2026-11-02T20:51:29.040079Z"}],"osv":[{"id":"CVE-2023-46250","title":"pypdf possible Infinite Loop when PdfWriter(clone_from) is used with a PDF","description":"pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions 3.7.0 through 3.16.4 can craft a PDF which leads to an infinite loop. This infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage. That is, for example, the case when the pypdf-user manipulates an incoming malicious PDF e.g. by merging it with another PDF or by adding annotations. The issue was fixed in version 3.17.0. As a workaround, apply the patch manually by modifying `pypdf/generic/_data_structures.py`.","status":"published","published":"2023-10-31T15:23:32.852Z","modified":"2026-11-04T02:46:10.837008209Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-835"],"updated_at":"2026-11-04T02:54:00.554175Z"},{"id":"GHSA-wjcc-cq79-p63f","title":"Possible Infinite Loop when PdfWriter(clone_from) is used with a PDF","description":"### Impact\nAn attacker who uses this vulnerability can craft a PDF which leads to an infinite loop.\nThis infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage.\n\nThat is, for example, the case when the pypdf-user manipulates an incoming malicious PDF e.g. by merging it with another PDF or by adding annotations.\n\n### Patches\nThe issue was fixed with #2264\n\n### Workarounds\nIf you cannot update your version of pypdf, you should modify `pypdf/generic/_data_structures.py` just like #2264 did.","status":"published","published":"2023-10-31T22:22:50Z","modified":"2026-09-10T03:50:08.746181393Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-835"],"updated_at":"2026-11-02T15:46:58.767335Z"},{"id":"PYSEC-2026-1834","title":"Possible Infinite Loop when PdfWriter(clone_from) is used with a PDF","description":"### Impact\nAn attacker who uses this vulnerability can craft a PDF which leads to an infinite loop.\nThis infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage.\n\nThat is, for example, the case when the pypdf-user manipulates an incoming malicious PDF e.g. by merging it with another PDF or by adding annotations.\n\n### Patches\nThe issue was fixed with #2264\n\n### Workarounds\nIf you cannot update your version of pypdf, you should modify `pypdf/generic/_data_structures.py` just like #2264 did.","status":"published","published":"2026-07-07T11:45:26.634787Z","modified":"2026-07-07T17:46:59.477344715Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:52:55.06457Z"},{"id":"UBUNTU-CVE-2023-46250","description":"pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions 3.7.0 through 3.16.4 can craft a PDF which leads to an infinite loop. This infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage. That is, for example, the case when the pypdf-user manipulates an incoming malicious PDF e.g. by merging it with another PDF or by adding annotations. The issue was fixed in version 3.17.0. As a workaround, apply the patch manually by modifying `pypdf/generic/_data_structures.py`.","status":"published","published":"2023-10-31T16:15:00Z","modified":"2026-10-17T12:56:25.895662336Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium"},{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T16:54:22.741943Z"}]}}