{"answers":{"affected":"3 open source packages ship an affected version, including httpx2.","exploited":"There is no known exploitation of CVE-2026-84378 in the wild and no public exploit code.","fix":"Upgrade httpx2 to 2.10.0 or later.","what":"CVE-2026-84378 is a medium-severity denial of service vulnerability in pydantic httpx2, published on 2 Sep 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-2026-84378 and fix it if it is affected.\n\nWhat it is: CVE-2026-84378 is a medium-severity denial of service vulnerability in pydantic httpx2, published on 2 Sep 2026. 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-2026-84378 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- httpx2 (PyPI): affected from 2.5.0; fixed in 2.10.0\n- httpx2 (PyPI): affected from 2.5.0; fixed in 2.10.0\n- httpx2 (PyPI): affected from 2.5.0; fixed in 2.10.0\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-2026-84378/ (Markdown: https://insights.sbomify.com/CVE-2026-84378/index.md)","id":"CVE-2026-84378","markdown":"https://insights.sbomify.com/CVE-2026-84378/index.md","name":"CVE-2026-84378","record":{"aliases":["DEBIAN-CVE-2026-84378","ECHO-e305-29d2-dcb3","GHSA-f2fp-rgf2-35cp","MINI-485q-xq5h-m8rc","PYSEC-2026-3847","UBUNTU-CVE-2026-84378"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Python HTTP client","requires_auth":"none","summary":"A crafted Server-Sent Events stream can cause quadratic CPU consumption in the HTTPX2 library, 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":[],"cvss":{"score":5.9,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-407","name":"Inefficient Algorithmic Complexity"}],"description":"HTTPX2 is a next generation HTTP client for Python. From 2.5.0 until 2.10.0, the HTTPX2 Server-Sent Events parser in src/httpx2/httpx2/_sse.py repeatedly copies and rescans buffered text in _SSELineDecoder.decode() when an attacker-controlled or compromised SSE endpoint splits one unterminated line across many response chunks. The behavior affects httpx2.Client.sse() and httpx2.AsyncClient.sse(), and the total processing work grows quadratically with the line length, allowing a crafted stream to consume excessive CPU and block a synchronous worker or asynchronous event loop. This issue is fixed in version 2.10.0.","ecosystems":["PyPI"],"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":"HTTPX2: Quadratic SSE line buffering can cause CPU denial of service","id":"CVE-2026-84378","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"PyPI","product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":3,"n_references":5,"next":{"headline":"HTTPX2: Multipart part header injection via unvalidated file Content-Type and custom headers","id":"CVE-2026-84379"},"packages":[{"ecosystem":"PyPI","fixed":["2.10.0"],"introduced":["2.5.0"],"last_affected":[],"package":"httpx2","purl":null,"source":"GHSA-f2fp-rgf2-35cp"},{"ecosystem":"PyPI","fixed":["2.10.0"],"introduced":["2.5.0"],"last_affected":[],"package":"httpx2","purl":"pkg:pypi/httpx2","source":"GHSA-f2fp-rgf2-35cp"},{"ecosystem":"PyPI","fixed":["2.10.0"],"introduced":["2.5.0"],"last_affected":[],"package":"httpx2","purl":"pkg:pypi/httpx2","source":"PYSEC-2026-3847"}],"prev":{"headline":"LiteLLM: Authenticated SSRF and provider-credential exfiltration via unvalidated request-body routing parameters","id":"CVE-2026-84377"},"products":["httpx2"],"published":"2026-09-02","related":[],"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":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-09-02","vendors":["pydantic"]},"summary":"A crafted Server-Sent Events stream can cause quadratic CPU consumption in the HTTPX2 library, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2026-84378/"}