{"answers":{"affected":"2 open source packages ship an affected version, including matrix-js-sdk. It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-40823 in the wild and no public exploit code.","fix":"Upgrade matrix-js-sdk to 12.4.1 or later.","what":"CVE-2021-40823 is a medium-severity vulnerability in n/a, published on 13 Sep 2021. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-40823 and fix it if it is affected.\n\nWhat it is: CVE-2021-40823 is a medium-severity vulnerability in n/a, published on 13 Sep 2021. 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-2021-40823 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- matrix-js-sdk (npm): affected all versions; fixed in 12.4.1\n- matrix-js-sdk (npm): affected all versions; fixed in 12.4.1\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-2021-40823/ (Markdown: https://insights.sbomify.com/CVE-2021-40823/index.md)","id":"CVE-2021-40823","markdown":"https://insights.sbomify.com/CVE-2021-40823/index.md","name":"CVE-2021-40823","record":{"aliases":["CLEANSTART-2024-FT51773","DEBIAN-CVE-2021-40823","GHSA-23cm-x6j7-6hq3","UBUNTU-CVE-2021-40823"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["data_read","security_bypass"],"network_reachable":"yes","non_default_config":false,"product_category":"Matrix JavaScript SDK","requires_auth":"none","summary":"A malicious homeserver can steal encryption keys from clients, allowing decryption of end-to-end encrypted messages in the Matrix JavaScript SDK.","user_interaction":"not_required","vuln_class":"business_logic"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"mitre","cpe":[{"product":"javascript_sdk","vendor":"matrix"}],"cvss":{"score":5.9,"severity":"medium","source":"nvd","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","version":"3.1"},"cwes":[{"id":"CWE-290","name":"Authentication Bypass by Spoofing"}],"description":"A logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12.4.1 allows a malicious Matrix homeserver present in an encrypted room to steal room encryption keys (via crafted Matrix protocol messages) that were originally sent by affected Matrix clients participating in that room. This allows the homeserver to decrypt end-to-end encrypted messages sent by affected clients.","ecosystems":["npm"],"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":"matrix-js-sdk can be tricked into disclosing E2EE room keys to a participating homeserver","id":"CVE-2021-40823","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":null,"products":[],"type":"business_logic","year":"2021"},"n_packages":2,"n_references":2,"next":{"headline":"Logic error in Matrix SDK for Android","id":"CVE-2021-40824"},"packages":[{"ecosystem":"npm","fixed":["12.4.1"],"introduced":["0"],"last_affected":[],"package":"matrix-js-sdk","purl":null,"source":"GHSA-23cm-x6j7-6hq3"},{"ecosystem":"npm","fixed":["12.4.1"],"introduced":["0"],"last_affected":[],"package":"matrix-js-sdk","purl":"pkg:npm/matrix-js-sdk","source":"GHSA-23cm-x6j7-6hq3"}],"prev":{"headline":"GeoServer allows SSRF via the option for setting a proxy host","id":"CVE-2021-40822"},"products":["n/a"],"published":"2021-09-13","related":[{"cvss_score":8.6,"headline":"Matrix JavaScript SDK vulnerable to key/device identifier confusion in SAS verification","id":"CVE-2022-39250","kev_date_added":null,"published":"2022-09-29"},{"cvss_score":8.6,"headline":"Matrix Javascript SDK vulnerable to Olm/Megolm protocol confusion","id":"CVE-2022-39251","kev_date_added":null,"published":"2022-09-28"},{"cvss_score":8.2,"headline":"Prototype pollution in matrix-js-sdk","id":"CVE-2022-36059","kev_date_added":null,"published":"2023-03-28"},{"cvss_score":8.2,"headline":"Prototype pollution in matrix-js-sdk","id":"CVE-2023-28427","kev_date_added":null,"published":"2023-03-28"},{"cvss_score":7.5,"headline":"Matrix Javascript SDK vulnerable to impersonation via forwarded Megolm sessions","id":"CVE-2022-39249","kev_date_added":null,"published":"2022-09-28"},{"cvss_score":5,"headline":"matrix-js-sdk vulnerable to invisible eavesdropping in group calls","id":"CVE-2023-29529","kev_date_added":null,"published":"2023-04-14"}],"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":"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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-04","vendors":["n/a"]},"summary":"A malicious homeserver can steal encryption keys from clients, allowing decryption of end-to-end encrypted messages in the Matrix JavaScript SDK.","url":"https://insights.sbomify.com/CVE-2021-40823/"}