{"id":"CVE-2025-66019","aliases":["CLSA-2026-1787843313","EUVD-2025-199017","GHSA-m449-cwjh-6pw7","PYSEC-2026-1832","UBUNTU-CVE-2025-66019","openSUSE-SU-2025:15776-1"],"status":"published","title":"pypdf manipulated LZWDecode streams can exhaust RAM","description":"pypdf is a free and open-source pure-python PDF library. Prior to version 6.4.0, an attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter. This issue has been patched in version 6.4.0.","severity":{"version":"4.0","score":6.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00387,"percentile":0.33098,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-400","CWE-409"],"published":"2025-11-24T22:42:07Z","modified":"2026-10-28T02:30:25Z","fixes":[{"ecosystem":"PyPI","package":"pypdf","fixed_in":["6.4.0"],"sources":["ghsa","osv"]},{"ecosystem":"openSUSE:Tumbleweed","package":"python-pypdf","fixed_in":["6.4.0-1.1"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"pypdf","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.4.0"}]}]},{"source":"osv","ecosystem":"TuxCare:PyPI","package":"pypdf","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.9.0"},{"fixed":"5.9.0.post16+tuxcare"}]}],"versions":["5.9.0","5.9.0.post1+tuxcare","5.9.0.post10+tuxcare","5.9.0.post11+tuxcare","5.9.0.post12+tuxcare","5.9.0.post13+tuxcare","5.9.0.post14+tuxcare","5.9.0.post15+tuxcare","5.9.0.post2+tuxcare","5.9.0.post3+tuxcare","5.9.0.post4+tuxcare","5.9.0.post5+tuxcare","5.9.0.post6+tuxcare","5.9.0.post7+tuxcare","5.9.0.post8+tuxcare","5.9.0.post9+tuxcare"],"bundled":10},{"source":"osv","ecosystem":"PyPI","package":"pypdf","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.4.0"}]}],"versions":["1.0","1.1","1.10","1.11","1.12","1.13","1.2","1.3","1.4","1.5","1.6","1.7","1.8","1.9","3.1.0","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","3.17.0","3.17.1","3.17.2","3.17.3","3.17.4","3.2.0","3.2.1","3.3.0","3.4.0","3.4.1","3.5.0","3.5.1","3.5.2","3.6.0","3.7.0","3.7.1","3.8.0","3.8.1","3.9.0","3.9.1","4.0.0","4.0.1","4.0.2","4.1.0","4.2.0","4.3.0","4.3.1","5.0.0","5.0.1","5.1.0","5.2.0","5.3.0","5.3.1","5.4.0","5.5.0","5.6.0","5.6.1","5.7.0","5.8.0","5.9.0","6.0.0","6.1.0","6.1.1","6.1.2","6.1.3","6.2.0","6.3.0"]},{"source":"osv","ecosystem":"PyPI","package":"pypdf","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.4.0"}]}],"versions":["1.0","1.1","1.10","1.11","1.12","1.13","1.2","1.3","1.4","1.5","1.6","1.7","1.8","1.9","3.1.0","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","3.17.0","3.17.1","3.17.2","3.17.3","3.17.4","3.2.0","3.2.1","3.3.0","3.4.0","3.4.1","3.5.0","3.5.1","3.5.2","3.6.0","3.7.0","3.7.1","3.8.0","3.8.1","3.9.0","3.9.1","4.0.0","4.0.1","4.0.2","4.1.0","4.2.0","4.3.0","4.3.1","5.0.0","5.0.1","5.1.0","5.2.0","5.3.0","5.3.1","5.4.0","5.5.0","5.6.0","5.6.1","5.7.0","5.8.0","5.9.0","6.0.0","6.1.0","6.1.1","6.1.2","6.1.3","6.2.0","6.3.0"]},{"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: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"]},{"source":"osv","ecosystem":"openSUSE:Tumbleweed","package":"python-pypdf","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.4.0-1.1"}]}]}],"products":[{"vendor":"py-pdf","product":"pypdf"}],"references":[{"url":"https://github.com/py-pdf/pypdf/security/advisories/GHSA-m449-cwjh-6pw7","tags":["x_refsource_CONFIRM","advisory","web","report"]},{"url":"https://github.com/py-pdf/pypdf/commit/96186725e5e6f237129a58a97cd19204a9ce40b2","tags":["x_refsource_MISC","fix","web","report"]},{"url":"https://github.com/py-pdf/pypdf/releases/tag/6.4.0","tags":["x_refsource_MISC","web","report"]},{"url":"https://aydinnyunus.github.io/2025/12/20/cve-2025-66019-pypdf-lzw-dos/","tags":["web"]},{"url":"https://github.com/py-pdf/pypdf/security/advisories/GHSA-jfx9-29x2-rv3j","tags":["web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-66019","tags":["advisory"]},{"url":"https://aydinnyunus.github.io/2025/12/20/cve-2025-66019-pypdf-lzw-dos","tags":["web"]},{"url":"https://github.com/advisories/GHSA-m449-cwjh-6pw7","tags":["advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/66xxx/CVE-2025-66019.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-2025-66019","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-66019","tags":["report"]},{"url":"","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2025-66019","tags":["web"]}],"sources":{"cve":[{"id":"CVE-2025-66019","title":"pypdf manipulated LZWDecode streams can exhaust RAM","description":"pypdf is a free and open-source pure-python PDF library. Prior to version 6.4.0, an attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter. This issue has been patched in version 6.4.0.","status":"published","published":"2025-11-25T23:38:12.473Z","modified":"2026-01-20T18:33:02.928Z","cvss":[{"version":"4.0","score":6.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U","level":"medium","assessor":"cna"}],"cwes":["CWE-400","CWE-409"],"updated_at":"2026-11-02T14:32:53.157279Z"}],"euvd":[{"id":"EUVD-2025-199017","description":"pypdf is a free and open-source pure-python PDF library. Prior to version 6.4.0, an attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter. This issue has been patched in version 6.4.0.","status":"published","published":"2025-11-25T23:38:12Z","modified":"2026-01-20T18:33:02Z","cvss":[{"version":"4.0","score":6.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U","level":"medium"}],"updated_at":"2026-11-02T19:48:49.964072Z"}],"ghsa":[{"id":"GHSA-m449-cwjh-6pw7","title":"pypdf's LZWDecode streams be manipulated to exhaust RAM","description":"### Impact\n\nAn attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter.\n\nThis is a follow up to [GHSA-jfx9-29x2-rv3j](https://github.com/py-pdf/pypdf/security/advisories/GHSA-jfx9-29x2-rv3j) to align the default limit with the one for *zlib*.\n\n### Patches\nThis has been fixed in [pypdf==6.4.0](https://github.com/py-pdf/pypdf/releases/tag/6.4.0).\n\n### Workarounds\nIf users cannot upgrade yet, use the line below to overwrite the default in their code:\n\n```python\npypdf.filters.LZW_MAX_OUTPUT_LENGTH = 75_000_000\n```","status":"published","published":"2025-11-24T22:42:07Z","modified":"2026-01-21T16:37:14Z","cvss":[{"version":"4.0","score":6.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U","level":"medium"}],"cwes":["CWE-400","CWE-409"],"updated_at":"2026-11-02T14:39:18.564331Z"}],"nvd":[{"id":"CVE-2025-66019","description":"pypdf is a free and open-source pure-python PDF library. Prior to version 6.4.0, an attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter. This issue has been patched in version 6.4.0.","status":"published","published":"2025-11-26T00:15:51.263Z","modified":"2026-10-19T13:10:00.11Z","cvss":[{"version":"4.0","score":6.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"}],"cwes":["CWE-400","CWE-409"],"updated_at":"2026-11-02T14:11:46.94029Z"}],"osv":[{"id":"CVE-2025-66019","title":"pypdf manipulated LZWDecode streams can exhaust RAM","description":"pypdf is a free and open-source pure-python PDF library. Prior to version 6.4.0, an attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter. This issue has been patched in version 6.4.0.","status":"published","published":"2025-11-25T23:38:12.473Z","modified":"2026-10-28T02:30:25.287128126Z","cvss":[{"version":"4.0","score":6.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U","level":"medium"}],"cwes":["CWE-400","CWE-409"],"updated_at":"2026-11-02T15:44:52.202386Z"},{"id":"GHSA-m449-cwjh-6pw7","title":"pypdf's LZWDecode streams be manipulated to exhaust RAM","description":"### Impact\n\nAn attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter.\n\nThis is a follow up to [GHSA-jfx9-29x2-rv3j](https://github.com/py-pdf/pypdf/security/advisories/GHSA-jfx9-29x2-rv3j) to align the default limit with the one for *zlib*.\n\n### Patches\nThis has been fixed in [pypdf==6.4.0](https://github.com/py-pdf/pypdf/releases/tag/6.4.0).\n\n### Workarounds\nIf users cannot upgrade yet, use the line below to overwrite the default in their code:\n\n```python\npypdf.filters.LZW_MAX_OUTPUT_LENGTH = 75_000_000\n```","status":"published","published":"2025-11-24T22:42:07Z","modified":"2026-09-10T03:50:31.107367078Z","cvss":[{"version":"4.0","score":6.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U","level":"medium"}],"cwes":["CWE-400","CWE-409"],"updated_at":"2026-11-02T15:46:51.10002Z"},{"id":"PYSEC-2026-1832","title":"pypdf's LZWDecode streams be manipulated to exhaust RAM","description":"### Impact\n\nAn attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter.\n\nThis is a follow up to [GHSA-jfx9-29x2-rv3j](https://github.com/py-pdf/pypdf/security/advisories/GHSA-jfx9-29x2-rv3j) to align the default limit with the one for *zlib*.\n\n### Patches\nThis has been fixed in [pypdf==6.4.0](https://github.com/py-pdf/pypdf/releases/tag/6.4.0).\n\n### Workarounds\nIf users cannot upgrade yet, use the line below to overwrite the default in their code:\n\n```python\npypdf.filters.LZW_MAX_OUTPUT_LENGTH = 75_000_000\n```","status":"published","published":"2026-07-07T16:03:10.809096Z","modified":"2026-07-07T17:46:59.109908172Z","cvss":[{"version":"4.0","score":6.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U","level":"medium"}],"updated_at":"2026-11-02T15:52:55.06457Z"},{"id":"UBUNTU-CVE-2025-66019","description":"pypdf is a free and open-source pure-python PDF library. Prior to version 6.4.0, an attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter. This issue has been patched in version 6.4.0.","status":"published","published":"2025-11-26T00:15:00Z","modified":"2026-10-17T12:57:28.308110234Z","cvss":[{"version":"4.0","score":6.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U","level":"medium"}],"updated_at":"2026-11-02T16:55:52.345622Z"},{"id":"CLSA-2026-1787843313","title":"TuxCare security update for pypdf (10 CVEs)","description":"TuxCare rebuilt pypdf to address 10 CVEs. Fixed in 5.9.0.post16+tuxcare.","status":"published","published":"2026-08-27T15:08:33Z","modified":"2026-10-15T09:48:05.735706677Z","updated_at":"2026-11-02T15:43:47.591214Z"},{"id":"openSUSE-SU-2025:15776-1","title":"python311-pypdf-6.4.0-1.1 on GA media","description":"These are all security issues fixed in the python311-pypdf-6.4.0-1.1 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2025-11-27T00:00:00Z","modified":"2026-03-23T04:54:11.449484Z","updated_at":"2026-11-02T16:58:38.101535Z"}]}}