{"answers":{"affected":"3 open source packages ship an affected version, including pyjwt. It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-48523 exists.","fix":"Upgrade pyjwt to a fixed version for your release line: 2.12.1 or 2.13.0.","what":"CVE-2026-48523 is a medium-severity vulnerability in jpadilla pyjwt, published on 28 May 2026. Any signed-in user can exploit it over the network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-48523 and fix it if it is affected.\n\nWhat it is: CVE-2026-48523 is a medium-severity vulnerability in jpadilla pyjwt, published on 28 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-48523 exists.\n\nAffected packages and fixed versions:\n- pyjwt (PyPI): affected from 2.9.0; fixed in 2.12.1\n- pyjwt (PyPI): affected from 2.9.0; fixed in 2.13.0\n- pyjwt (PyPI): affected from 2.9.0; fixed in 2.13.0\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-2026-48523/ (Markdown: https://insights.sbomify.com/CVE-2026-48523/index.md)","id":"CVE-2026-48523","markdown":"https://insights.sbomify.com/CVE-2026-48523/index.md","name":"CVE-2026-48523","record":{"aliases":["BELL-CVE-2026-48523","CLEANSTART-2026-HM72127","DEBIAN-CVE-2026-48523","ECHO-894a-8fa2-a1b5","GHSA-jq35-7prp-9v3f","MINI-2p3c-ghvh-749x","MINI-4hxm-pmvv-mmw4","MINI-5mcj-493v-gjcm","MINI-5q79-p9jf-275v","MINI-5w8x-8qrj-pq6m","MINI-6xfh-8ggj-fq62","MINI-78jg-gwjf-rr97","MINI-799g-23pr-hggr","MINI-7x5h-fgqq-8q8r","MINI-9wrv-v6ww-4frp","MINI-c5m7-m26g-47hr","MINI-c6jm-cwfc-22jp","MINI-crh8-qmvq-q696","MINI-f67x-h2h8-hx9w","MINI-f8qm-48rw-cp4h","MINI-gmx6-48w4-fj64","MINI-h2h2-h868-wcgg","MINI-h778-34h4-5q7x","MINI-hg72-fjw9-rghj","MINI-j7pm-xj95-5wh9","MINI-m36h-hvqr-x3fx","MINI-m3r3-8w22-88gp","MINI-pp8r-r9qq-jg6c","MINI-prh3-67pp-rc4m","MINI-q67r-r565-xgmc","MINI-rp2m-6q22-vx9p","MINI-wqqx-8847-4j4q","MINI-wv3w-vrrx-x9w6","PYSEC-2026-176","ROOT-APP-PYPI-CVE-2026-48523","UBUNTU-CVE-2026-48523"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["security_bypass"],"network_reachable":"yes","non_default_config":false,"product_category":"Python JWT library","requires_auth":"low_privilege","summary":"Attackers can bypass JWT algorithm allow-lists when using PyJWK keys, allowing tokens signed with disallowed algorithms to be accepted as valid.","user_interaction":"not_required","vuln_class":"security_feature_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"pyjwt","vendor":"pyjwt_project"}],"cvss":{"score":5.4,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-347","name":"Improper Verification of Cryptographic Signature"}],"description":"PyJWT is a JSON Web Token implementation in Python. From 2.9.0 to 2.12.1, there is a verifier-side algorithm allow-list bypass when jwt.decode() or jwt.decode_complete() are called with a PyJWK key. The token header alg is checked against the caller-supplied algorithms allow-list, but signature verification is performed with the algorithm bound to the PyJWK object instead of the header algorithm. An attacker who controls a registered JWK/JWKS private key can sign with a disallowed algorithm, advertise an allowed algorithm in the JWT header, and still be accepted. The issue affects the documented PyJWKClient.get_signing_key_from_jwt(...) flow. This vulnerability is fixed in 2.13.0.","ecosystems":["PyPI"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"PyJWT: Algorithm allow-list bypass when decoding with `PyJWK` / `PyJWKClient` keys","id":"CVE-2026-48523","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"PyPI","product":null,"products":[],"type":"security_feature_bypass","year":"2026"},"n_packages":3,"n_references":1,"next":{"headline":"PyJWT: PyJWKClient unbounded JWKS endpoint requests via attacker-controlled kid values (DoS)","id":"CVE-2026-48524"},"packages":[{"ecosystem":"PyPI","fixed":["2.12.1"],"introduced":["2.9.0"],"last_affected":[],"package":"pyjwt","purl":"pkg:pypi/pyjwt","source":"PYSEC-2026-176"},{"ecosystem":"PyPI","fixed":["2.13.0"],"introduced":["2.9.0"],"last_affected":[],"package":"pyjwt","purl":null,"source":"GHSA-jq35-7prp-9v3f"},{"ecosystem":"PyPI","fixed":["2.13.0"],"introduced":["2.9.0"],"last_affected":[],"package":"pyjwt","purl":"pkg:pypi/pyjwt","source":"GHSA-jq35-7prp-9v3f"}],"prev":{"headline":"PyJWKClient: missing scheme allowlist enables SSRF + token forgery via file://, ftp://, data: schemes","id":"CVE-2026-48522"},"products":["pyjwt"],"published":"2026-05-28","related":[{"cvss_score":9.1,"headline":"PyJWT: Asymmetric-PEM detection bypass: whitespace/line-ending-mutated public keys skip the HS/asymmetric confusion guard","id":"CVE-2026-102268","kev_date_added":null,"published":"2026-09-28"},{"cvss_score":7.5,"headline":"PyJWT accepts unknown `crit` header extensions (RFC 7515 §4.1.11 MUST violation)","id":"CVE-2026-32597","kev_date_added":null,"published":"2026-03-12"},{"cvss_score":7.4,"headline":"PyJWK accepts empty HMAC keys, bypassing PyJWT's empty-key validation","id":"CVE-2026-102266","kev_date_added":null,"published":"2026-09-28"},{"cvss_score":7.4,"headline":"PyJWT: PyJWKClient follows redirects when fetching JWKS","id":"CVE-2026-102267","kev_date_added":null,"published":"2026-09-28"},{"cvss_score":7.4,"headline":"PyJWT: Public keys in DER form are accepted as HMAC secrets, bypassing the CVE-2022-29217 guard","id":"CVE-2026-102271","kev_date_added":null,"published":"2026-09-28"},{"cvss_score":7.4,"headline":"PyJWT BOM Bypass","id":"CVE-2026-102272","kev_date_added":null,"published":"2026-09-28"},{"cvss_score":7.4,"headline":"PyJWT accepts public JWK containers as HMAC secrets","id":"CVE-2026-102273","kev_date_added":null,"published":"2026-09-28"}],"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":"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":"no","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-28","vendors":["jpadilla"]},"summary":"Attackers can bypass JWT algorithm allow-lists when using PyJWK keys, allowing tokens signed with disallowed algorithms to be accepted as valid.","url":"https://insights.sbomify.com/CVE-2026-48523/"}