{"answers":{"affected":"3 open source packages ship an affected version, including urllib3. It affects 1 product.","exploited":"There is no known exploitation of CVE-2025-66418 in the wild and no public exploit code.","fix":"Upgrade urllib3 to 2.6.0 or later.","what":"CVE-2025-66418 is a high-severity denial of service vulnerability in urllib3, published on 5 Dec 2025. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2025-66418 and fix it if it is affected.\n\nWhat it is: CVE-2025-66418 is a high-severity denial of service vulnerability in urllib3, published on 5 Dec 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2025-66418 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- urllib3 (PyPI): affected from 1.24; fixed in 2.6.0\n- urllib3 (PyPI): affected from 1.24; fixed in 2.6.0\n- urllib3 (PyPI): affected from 1.24; fixed in 2.6.0\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2025-66418/ (Markdown: https://insights.sbomify.com/CVE-2025-66418/index.md)","id":"CVE-2025-66418","markdown":"https://insights.sbomify.com/CVE-2025-66418/index.md","name":"CVE-2025-66418","record":{"aliases":["ALPINE-CVE-2025-66418","AZL-71834","AZL-71846","BELL-CVE-2025-66418","CLEANSTART-2026-GI63491","DEBIAN-CVE-2025-66418","ECHO-2d1b-2193-003f","GHSA-gm62-xv2j-4w53","MINI-2cfp-mr5p-v9xh","MINI-2j5j-mx6v-5v36","MINI-48c8-v3h8-88pj","MINI-7fh3-8hwm-xq38","MINI-86rf-527g-vj73","MINI-8p4j-jxf7-qm55","MINI-cc7r-3x5v-c76p","MINI-cw83-g2m8-hqfv","MINI-fcqc-vwm2-6257","MINI-m2f3-vrqw-wh79","MINI-qqqr-7wqv-2qf5","MINI-v6wh-6pjc-26fj","MINI-vq9w-8629-wf7g","OESA-2026-1233","OESA-2026-1234","OESA-2026-1235","OESA-2026-1252","OESA-2026-1253","OESA-2026-1332","OESA-2026-1333","PYSEC-2026-1998","RHSA-2026:1329","RHSA-2026:1330","RHSA-2026:1331","RHSA-2026:1332","RHSA-2026:1336","RHSA-2026:1337","RHSA-2026:1338","RHSA-2026:1339","RHSA-2026:1340","RHSA-2026:1701","RHSA-2026:1702","RHSA-2026:2279","ROOT-APP-PYPI-CVE-2025-66418","ROOT-OS-UBUNTU-2204-CVE-2025-66418","UBUNTU-CVE-2025-66418","USN-8010-1","openSUSE-SU-2026:10431-1"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Python HTTP client library","requires_auth":"none","summary":"A malicious server can cause high CPU and memory usage in urllib3 by sending an unbounded decompression chain, leading to denial of service.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"urllib3","vendor":"python"}],"cvss":{"score":8.9,"severity":"high","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H","version":"4.0"},"cwes":[{"id":"CWE-770","name":"Allocation of Resources Without Limits or Throttling"}],"description":"urllib3 is a user-friendly HTTP client library for Python. Starting in version 1.24 and prior to 2.6.0, the number of links in the decompression chain was unbounded allowing a malicious server to insert a virtually unlimited number of compression steps leading to high CPU usage and massive memory allocation for the decompressed data. This vulnerability is fixed in 2.6.0.","ecosystems":["PyPI","Red Hat:enterprise_linux:7::server","Red Hat:rhel_aus:8.4::appstream","Red Hat:rhel_aus:8.4::highavailability","Red Hat:rhel_aus:8.6::appstream","Red Hat:rhel_e4s:8.6::appstream","Red Hat:rhel_e4s:8.6::highavailability","Red Hat:rhel_e4s:8.8::appstream","Red Hat:rhel_e4s:8.8::highavailability","Red Hat:rhel_e4s:9.0::appstream","Red Hat:rhel_e4s:9.0::highavailability","Red Hat:rhel_e4s:9.0::resilientstorage","Red Hat:rhel_e4s:9.2::appstream","Red Hat:rhel_e4s:9.2::highavailability","Red Hat:rhel_e4s:9.2::resilientstorage","Red Hat:rhel_eus:9.4::appstream","Red Hat:rhel_eus:9.4::highavailability","Red Hat:rhel_eus:9.4::resilientstorage","Red Hat:rhel_eus:9.6::appstream","Red Hat:rhel_eus_long_life:8.4::appstream","Red Hat:rhel_eus_long_life:8.4::highavailability","Red Hat:rhel_extras_sap_els:7","Red Hat:rhel_extras_sap_hana_els:7","Red Hat:rhel_tus:8.6::appstream","Red Hat:rhel_tus:8.6::highavailability","Red Hat:rhel_tus:8.8::appstream","Red Hat:rhel_tus:8.8::highavailability","openSUSE:Tumbleweed"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"urllib3 allows an unbounded number of links in the decompression chain","id":"CVE-2025-66418","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"PyPI","product":null,"products":[],"type":"denial_of_service","year":"2025"},"n_packages":922,"n_references":2,"next":{"headline":"MaxKB vulnerable to privilege escalation through sandbox bypass","id":"CVE-2025-66419"},"packages":[{"ecosystem":"PyPI","fixed":["2.6.0"],"introduced":["1.24"],"last_affected":[],"package":"urllib3","purl":null,"source":"GHSA-gm62-xv2j-4w53"},{"ecosystem":"PyPI","fixed":["2.6.0"],"introduced":["1.24"],"last_affected":[],"package":"urllib3","purl":"pkg:pypi/urllib3","source":"GHSA-gm62-xv2j-4w53"},{"ecosystem":"PyPI","fixed":["2.6.0"],"introduced":["1.24"],"last_affected":[],"package":"urllib3","purl":"pkg:pypi/urllib3","source":"PYSEC-2026-1998"},{"ecosystem":"Red Hat:enterprise_linux:7::server","fixed":["0:0.1.13-1.el7_9.3"],"introduced":["0"],"last_affected":[],"package":"python-s3transfer","purl":"pkg:rpm/redhat/python-s3transfer","source":"RHSA-2026:1337"},{"ecosystem":"Red Hat:enterprise_linux:7::server","fixed":["0:4.1.1-61.el7_9.21"],"introduced":["0"],"last_affected":[],"package":"resource-agents","purl":"pkg:rpm/redhat/resource-agents","source":"RHSA-2026:1336"},{"ecosystem":"Red Hat:enterprise_linux:7::server","fixed":["0:4.1.1-61.el7_9.21"],"introduced":["0"],"last_affected":[],"package":"resource-agents-aliyun","purl":"pkg:rpm/redhat/resource-agents-aliyun","source":"RHSA-2026:1336"},{"ecosystem":"Red Hat:enterprise_linux:7::server","fixed":["0:4.1.1-61.el7_9.21"],"introduced":["0"],"last_affected":[],"package":"resource-agents-debuginfo","purl":"pkg:rpm/redhat/resource-agents-debuginfo","source":"RHSA-2026:1336"},{"ecosystem":"Red Hat:enterprise_linux:7::server","fixed":["0:4.1.1-61.el7_9.21"],"introduced":["0"],"last_affected":[],"package":"resource-agents-gcp","purl":"pkg:rpm/redhat/resource-agents-gcp","source":"RHSA-2026:1336"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents","purl":"pkg:rpm/redhat/fence-agents","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-aliyun-debuginfo","purl":"pkg:rpm/redhat/fence-agents-aliyun-debuginfo","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-all","purl":"pkg:rpm/redhat/fence-agents-all","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-amt-ws","purl":"pkg:rpm/redhat/fence-agents-amt-ws","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-apc","purl":"pkg:rpm/redhat/fence-agents-apc","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-apc-snmp","purl":"pkg:rpm/redhat/fence-agents-apc-snmp","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-bladecenter","purl":"pkg:rpm/redhat/fence-agents-bladecenter","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-brocade","purl":"pkg:rpm/redhat/fence-agents-brocade","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-cisco-mds","purl":"pkg:rpm/redhat/fence-agents-cisco-mds","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-cisco-ucs","purl":"pkg:rpm/redhat/fence-agents-cisco-ucs","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-common","purl":"pkg:rpm/redhat/fence-agents-common","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-compute","purl":"pkg:rpm/redhat/fence-agents-compute","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-debuginfo","purl":"pkg:rpm/redhat/fence-agents-debuginfo","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-debugsource","purl":"pkg:rpm/redhat/fence-agents-debugsource","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-drac5","purl":"pkg:rpm/redhat/fence-agents-drac5","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-eaton-snmp","purl":"pkg:rpm/redhat/fence-agents-eaton-snmp","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-emerson","purl":"pkg:rpm/redhat/fence-agents-emerson","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-eps","purl":"pkg:rpm/redhat/fence-agents-eps","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-heuristics-ping","purl":"pkg:rpm/redhat/fence-agents-heuristics-ping","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-hpblade","purl":"pkg:rpm/redhat/fence-agents-hpblade","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-ibm-powervs","purl":"pkg:rpm/redhat/fence-agents-ibm-powervs","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-ibm-vpc","purl":"pkg:rpm/redhat/fence-agents-ibm-vpc","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-ibmblade","purl":"pkg:rpm/redhat/fence-agents-ibmblade","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-ifmib","purl":"pkg:rpm/redhat/fence-agents-ifmib","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-ilo-moonshot","purl":"pkg:rpm/redhat/fence-agents-ilo-moonshot","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-ilo-mp","purl":"pkg:rpm/redhat/fence-agents-ilo-mp","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-ilo-ssh","purl":"pkg:rpm/redhat/fence-agents-ilo-ssh","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-ilo2","purl":"pkg:rpm/redhat/fence-agents-ilo2","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-intelmodular","purl":"pkg:rpm/redhat/fence-agents-intelmodular","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-ipdu","purl":"pkg:rpm/redhat/fence-agents-ipdu","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-ipmilan","purl":"pkg:rpm/redhat/fence-agents-ipmilan","source":"RHSA-2026:2279"},{"ecosystem":"Red Hat:rhel_aus:8.4::appstream","fixed":["0:4.2.1-65.el8_4.24"],"introduced":["0"],"last_affected":[],"package":"fence-agents-kdump","purl":"pkg:rpm/redhat/fence-agents-kdump","source":"RHSA-2026:2279"}],"prev":{"headline":"GLPI has an unauthenticated SQL injection through the inventory endpoint","id":"CVE-2025-66417"},"products":["urllib3"],"published":"2025-12-05","related":[{"cvss_score":8.9,"headline":"urllib3: HTTPResponse.stream()/read_chunked() buffers an unbounded chunk-size line into memory","id":"CVE-2026-97689","kev_date_added":null,"published":"2026-09-29"},{"cvss_score":8.9,"headline":"urllib3: Decompression-bomb safeguards bypassed in parts of the streaming API","id":"CVE-2026-44432","kev_date_added":null,"published":"2026-05-13"},{"cvss_score":8.9,"headline":"urllib3 vulnerable to decompression-bomb safeguard bypass when following HTTP redirects (streaming API)","id":"CVE-2026-21441","kev_date_added":null,"published":"2026-01-07"},{"cvss_score":8.9,"headline":"urllib3 Streaming API improperly handles highly compressed data","id":"CVE-2025-66471","kev_date_added":null,"published":"2025-12-05"},{"cvss_score":8.2,"headline":"urllib3: Sensitive headers forwarded across origins in proxied low-level redirects","id":"CVE-2026-44431","kev_date_added":null,"published":"2026-05-13"},{"cvss_score":7.6,"headline":"urllib3: HTTPS proxy TLS configuration may be ignored or overridden","id":"CVE-2026-97687","kev_date_added":null,"published":"2026-09-29"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"PyPA Advisory Database","prefix":"PYSEC"},{"class":"attribution","licence":"CC BY 4.0","name":"Red Hat","prefix":"RHSA"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2025-12-05","vendors":["urllib3"]},"summary":"A malicious server can cause high CPU and memory usage in urllib3 by sending an unbounded decompression chain, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2025-66418/"}