{"answers":{"affected":"3 open source packages ship an affected version, including bandit. It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-39803 exists.","fix":"Upgrade bandit to 1.11.1 or later.","what":"CVE-2026-39803 is a high-severity denial of service vulnerability in mtrudel bandit, published on 13 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-39803 and fix it if it is affected.\n\nWhat it is: CVE-2026-39803 is a high-severity denial of service vulnerability in mtrudel bandit, published on 13 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-39803 exists.\n\nAffected packages and fixed versions:\n- bandit (Hex): affected from 1.4.0; fixed in 1.11.1\n- bandit (Hex): affected from 1.4.0; fixed in 1.11.1\n- bandit (Hex): affected from 1.4.0; fixed in 1.11.1\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-2026-39803/ (Markdown: https://insights.sbomify.com/CVE-2026-39803/index.md)","id":"CVE-2026-39803","markdown":"https://insights.sbomify.com/CVE-2026-39803/index.md","name":"CVE-2026-39803","record":{"aliases":["EEF-CVE-2026-39803","GHSA-9q9q-324x-93r2"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Elixir HTTP server","requires_auth":"none","summary":"Unauthenticated attackers can cause denial of service via memory exhaustion in the Bandit Elixir library by sending large chunked HTTP requests.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"EEF","cpe":[{"product":"bandit","vendor":"mtrudel"}],"cvss":{"score":8.7,"severity":"high","source":"cna","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","version":"4.0"},"cwes":[{"id":"CWE-770","name":"Allocation of Resources Without Limits or Throttling"}],"description":"Allocation of Resources Without Limits or Throttling vulnerability in mtrudel bandit allows unauthenticated remote denial of service via memory exhaustion.\n\nThe chunked clause of 'Elixir.Bandit.HTTP1.Socket':read_data/2 in lib/bandit/http1/socket.ex ignores the caller-supplied :length option when reading HTTP/1 chunked request bodies. Instead of capping the accumulated body at the configured limit (e.g. Plug.Parsers' default 8 MB), do_read_chunked_data!/5 buffers every received chunk into an iolist unconditionally and materializes the entire body as a single binary. The function always returns {:ok, body, ...}, so callers cannot interpose a 413 response.\n\nBecause Plug.Parsers runs before routing and authentication in the standard Phoenix endpoint, an unauthenticated attacker needs no valid route or credentials. Sending a single Transfer-Encoding: chunked POST request with an arbitrarily large body to any path causes the BEAM process to exhaust available memory and be terminated by the OS OOM killer.\n\nThe content-length path in the same function correctly enforces the limit and is not affected.\n\nThis issue affects bandit: from 1.4.0 before 1.11.1.","ecosystems":["Hex"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"HTTP/1 chunked body reader ignores length cap in bandit","id":"CVE-2026-39803","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Hex","product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":3,"n_references":4,"next":{"headline":"WebSocket permessage-deflate inflate has no output-size cap in bandit","id":"CVE-2026-39804"},"packages":[{"ecosystem":"Hex","fixed":["1.11.1"],"introduced":["1.4.0"],"last_affected":[],"package":"bandit","purl":"pkg:hex/bandit","source":"EEF-CVE-2026-39803"},{"ecosystem":"Hex","fixed":["1.11.1"],"introduced":["1.4.0"],"last_affected":[],"package":"bandit","purl":null,"source":"GHSA-9q9q-324x-93r2"},{"ecosystem":"Hex","fixed":["1.11.1"],"introduced":["1.4.0"],"last_affected":[],"package":"bandit","purl":"pkg:hex/bandit","source":"GHSA-9q9q-324x-93r2"}],"prev":{"headline":"WordPress Everest Backup plugin \u003c= 2.3.13 - Remote Code Execution (RCE) vulnerability","id":"CVE-2026-39802"},"products":["bandit"],"published":"2026-05-13","related":[{"cvss_score":8.7,"headline":"HTTP/1 chunked decoder infinite loop on requests with trailer fields in bandit","id":"CVE-2026-39806","kev_date_added":null,"published":"2026-05-13"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"Erlang Ecosystem Foundation","prefix":"EEF"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"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":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-27","vendors":["mtrudel"]},"summary":"Unauthenticated attackers can cause denial of service via memory exhaustion in the Bandit Elixir library by sending large chunked HTTP requests.","url":"https://insights.sbomify.com/CVE-2026-39803/"}