{"answers":{"affected":"1 open source package ship an affected version, including bandit.","exploited":"There is no known exploitation of CVE-2026-109584 in the wild and no public exploit code.","fix":"Upgrade bandit to 1.14.0 or later.","what":"CVE-2026-109584 is a high-severity vulnerability in mtrudel bandit, published on 26 Oct 2026."},"fix_prompt":"Check this codebase for CVE-2026-109584 and fix it if it is affected.\n\nWhat it is: CVE-2026-109584 is a high-severity vulnerability in mtrudel bandit, published on 26 Oct 2026. \nExploitation: There is no known exploitation of CVE-2026-109584 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- bandit (Hex): affected from 0.3.3; fixed in 1.14.0\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-2026-109584/ (Markdown: https://insights.sbomify.com/CVE-2026-109584/index.md)","id":"CVE-2026-109584","markdown":"https://insights.sbomify.com/CVE-2026-109584/index.md","name":"CVE-2026-109584","record":{"aliases":["EEF-CVE-2026-109584","GHSA-7gfj-7gvq-3xqj","UBUNTU-CVE-2026-109584"],"analysis":null,"analysis_generated_by":null,"assigner":"EEF","cpe":[],"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-409","name":"Improper Handling of Highly Compressed Data (Data Amplification)"}],"description":"Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in the HTTP/2 implementation of mtrudel bandit allows an unauthenticated remote attacker to exhaust server memory via a small HPACK-compressed HEADERS block. The block stores one large cookie value in the HPACK dynamic table and then references it tens of thousands of times with 1-byte indexed fields. In the reporter's run, a 49 KB block made a server with default settings allocate a 183 MB cookie binary before any application code ran, and every concurrent stream can repeat the cost.\n\nBandit.HTTP2.Connection caps only the compressed block (max_header_block_size), and its check of the decoded list against max_header_list_size never fires because that setting defaults to :infinity. combine_cookie_crumbs/1 in lib/bandit/http2/stream.ex then joins every crumb into one binary.\n\nThis issue affects bandit: from 0.3.3 before 1.14.0.","ecosystems":["Hex"],"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":"HTTP/2 cookie crumb join expands a small HPACK header block into an unbounded allocation in Bandit","id":"CVE-2026-109584","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Hex","product":null,"products":[],"type":null,"year":"2026"},"n_packages":1,"n_references":5,"next":{"headline":"Incorrect authorization in the Arm Cortex-R82 MPU port in FreeRTOS-Kernel","id":"CVE-2026-109587"},"packages":[{"ecosystem":"Hex","fixed":["1.14.0"],"introduced":["0.3.3"],"last_affected":[],"package":"bandit","purl":"pkg:hex/bandit","source":"EEF-CVE-2026-109584"}],"prev":{"headline":"HMS Networks PEAK-System PCAN Windows drivers Out-of-bounds Write","id":"CVE-2026-109576"},"products":["bandit"],"published":"2026-10-26","related":[],"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":"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":"2026-10-26","vendors":["mtrudel"]},"summary":null,"url":"https://insights.sbomify.com/CVE-2026-109584/"}