{"answers":{"affected":"3 open source packages ship an affected version, including oauthlib.","exploited":"There is no known exploitation of CVE-2026-49265 in the wild and no public exploit code.","fix":"Upgrade oauthlib to 4.0.0 or later.","what":"CVE-2026-49265 is a medium-severity vulnerability in oauthlib, published on 13 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-49265 and fix it if it is affected.\n\nWhat it is: CVE-2026-49265 is a medium-severity vulnerability in oauthlib, published on 13 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.\nExploitation: There is no known exploitation of CVE-2026-49265 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- oauthlib (PyPI): affected from 3.0.0; fixed in 4.0.0\n- oauthlib (PyPI): affected from 3.0.0; fixed in 4.0.0\n- oauthlib (PyPI): affected from 3.0.0; fixed in 4.0.0\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-2026-49265/ (Markdown: https://insights.sbomify.com/CVE-2026-49265/index.md)","id":"CVE-2026-49265","markdown":"https://insights.sbomify.com/CVE-2026-49265/index.md","name":"CVE-2026-49265","record":{"aliases":["AZL-108045","CLEANSTART-2026-NO84858","CLEANSTART-2026-PQ13819","CLEANSTART-2026-ZA90599","DEBIAN-CVE-2026-49265","ECHO-e653-cb4c-55e4","GHSA-xpv3-w29h-x7cv","MINI-2v7c-jjpm-3w7c","MINI-53h7-j5h7-2hph","MINI-5x7v-qvf5-w7x9","MINI-69rq-gjc9-c2c5","MINI-6jmr-26v5-98gf","MINI-8f6j-fq6m-mwpf","MINI-g72g-rgvg-8mrq","MINI-g7qf-4qhw-prm3","MINI-gh99-523h-7836","MINI-grq2-rff9-gwgh","MINI-gx77-39x6-h8f7","MINI-h6w3-284m-9c2j","MINI-jj7q-35x5-4p5p","MINI-m4wx-v4r8-fjhw","MINI-q97p-jgp3-qvg4","MINI-rpcc-rm3g-x65v","MINI-rpmh-vpgp-hvq7","MINI-vw88-7mgc-wr36","MINI-w287-3qp2-p528","MINI-wj73-qq63-vvfm","MINI-wm32-mj95-j6pq","MINI-wxp2-xhf5-6c2q","MINI-x8w3-p25j-mw36","MINI-xp9j-pwrj-4cr9","PYSEC-2026-4114","UBUNTU-CVE-2026-49265"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["data_read","account_takeover"],"network_reachable":"yes","non_default_config":false,"product_category":"Python OAuth library","requires_auth":"none","summary":"Timing side-channel in OAuthLib PKCE verification allows potential recovery of code_verifier, leading to unauthorized access token acquisition and account takeover.","user_interaction":"required","vuln_class":"information_disclosure"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":6.8,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N","version":"3.1"},"cwes":[{"id":"CWE-208","name":"Observable Timing Discrepancy"}],"description":"OAuthLib is an implementation of the OAuth request-signing logic for Python 3.6+. From 3.0.0 until 4.0.0, OAuthLib's PKCE checks in oauthlib/oauth2/rfc6749/grant_types/authorization_code.py compare attacker-supplied code_verifier values with stored challenges using ordinary string equality in code_challenge_method_plain and code_challenge_method_s256. Because the comparison can return after a length difference or the first mismatching character, repeated token endpoint measurements can reveal common-prefix timing information that could potentially allow recovery of the code_verifier, unauthorized access-token acquisition, and account takeover. Practical exploitation requires an intercepted, single-use authorization code and enough measurements to overcome real-world network noise; the local timing benchmark does not establish practical remote account takeover, so the weakness remains a defense-in-depth concern. This issue is fixed in version 4.0.0.","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":"OAuthLib: Timing Attack Vulnerability in PKCE code_verifier Comparison","id":"CVE-2026-49265","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"PyPI","product":null,"products":[],"type":"information_disclosure","year":"2026"},"n_packages":3,"n_references":5,"next":{"headline":"Apache Airflow: No certificate validation on SMTP STARTTLS connections","id":"CVE-2026-49267"},"packages":[{"ecosystem":"PyPI","fixed":["4.0.0"],"introduced":["3.0.0"],"last_affected":[],"package":"oauthlib","purl":null,"source":"GHSA-xpv3-w29h-x7cv"},{"ecosystem":"PyPI","fixed":["4.0.0"],"introduced":["3.0.0"],"last_affected":[],"package":"oauthlib","purl":"pkg:pypi/oauthlib","source":"GHSA-xpv3-w29h-x7cv"},{"ecosystem":"PyPI","fixed":["4.0.0"],"introduced":["3.0.0"],"last_affected":[],"package":"oauthlib","purl":"pkg:pypi/oauthlib","source":"PYSEC-2026-4114"}],"prev":{"headline":"OAuthLib: Unsafe JSONP callback injection in RevocationEndpoint allows arbitrary JavaScript response generation","id":"CVE-2026-49264"},"products":["oauthlib"],"published":"2026-10-13","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":"total"},"state":"PUBLISHED","updated":"2026-10-13","vendors":["oauthlib"]},"summary":"Timing side-channel in OAuthLib PKCE verification allows potential recovery of code_verifier, leading to unauthorized access token acquisition and account takeover.","url":"https://insights.sbomify.com/CVE-2026-49265/"}