{"id":"CVE-2026-111101","revision":"af169b7670e242c6a12b65900169bc4d","records":[{"revision":"af169b7670e242c6a12b65900169bc4d","observedAt":"2026-10-26T16:35:30.797+00:00","statement":{"source":"cve-program","id":"CVE-2026-111101","aliases":[],"title":"HTTP/1.1 chunked request bodies made of 1-byte chunks amplify memory use in Bandit","description":"Allocation of Resources Without Limits or Throttling vulnerability in the HTTP/1.1 chunked body reader of mtrudel bandit allows an unauthenticated remote attacker to exhaust server memory and CPU via a request body made of many 1-byte chunks.\n\nThe chunked reader in lib/bandit/http1/socket.ex keeps every chunk as its own list cell and binary term until IO.iodata_to_binary/1 joins them, and nothing limits the number of chunks. The :length option of read_body/2 counts only data bytes, so tiny chunks cost far more memory than their payload: 48 MB of 1-byte chunks grew one handler process to about 500 MB and took about 6 s of CPU. The route does not need to read the body, because on keep-alive connections ensure_completed/1 drains unread bodies through the same reader.\n\nThis issue affects bandit: from 0.1.0 before 1.14.0.","state":0,"publishedAt":"2026-10-26T13:31:48.184+00:00","modifiedAt":"2026-10-26T15:35:51.401+00:00","affected":[{"ecosystem":"https://repo.hex.pm","name":"bandit","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"collectionURL\": \"https://repo.hex.pm\",\n                    \"cpes\": [\n                        \"cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*\"\n                    ],\n                    \"defaultStatus\": \"unaffected\",\n                    \"packageName\": \"bandit\",\n                    \"packageURL\": \"pkg:hex/bandit\",\n                    \"product\": \"bandit\",\n                    \"repo\": \"https://github.com/mtrudel/bandit\",\n                    \"vendor\": \"mtrudel\",\n                    \"versions\": [\n                        {\n                            \"lessThan\": \"1.14.0\",\n                            \"status\": \"affected\",\n                            \"version\": \"0.1.0\",\n                            \"versionType\": \"semver\"\n                        }\n                    ]\n                }"},{"ecosystem":"https://github.com","name":"mtrudel/bandit","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"collectionURL\": \"https://github.com\",\n                    \"cpes\": [\n                        \"cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*\"\n                    ],\n                    \"defaultStatus\": \"unaffected\",\n                    \"packageName\": \"mtrudel/bandit\",\n                    \"packageURL\": \"pkg:github/mtrudel/bandit\",\n                    \"product\": \"bandit\",\n                    \"repo\": \"https://github.com/mtrudel/bandit\",\n                    \"vendor\": \"mtrudel\",\n                    \"versions\": [\n                        {\n                            \"lessThan\": \"220b9dfd27f9a21305be2afc75cbe585ddc24e7a\",\n                            \"status\": \"affected\",\n                            \"version\": \"7201270c34b90f6c9e15c0386c2bb802c0c72ab4\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","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","score":8.7,"severity":"HIGH"}],"references":["https://github.com/mtrudel/bandit/security/advisories/GHSA-jwh3-j29h-qfmw","https://cna.erlef.org/cves/CVE-2026-111101.html","https://osv.dev/vulnerability/EEF-CVE-2026-111101","https://github.com/mtrudel/bandit/commit/7201270c34b90f6c9e15c0386c2bb802c0c72ab4","https://github.com/mtrudel/bandit/commit/220b9dfd27f9a21305be2afc75cbe585ddc24e7a"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-111101","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-111101","identifiers":["CVE-2026-111101"]},"retained":false,"historicalAffected":[]}],"coverage":[]}