{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-81520 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2026-81520 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-81520 is a high-severity denial of service vulnerability in MongoDB BI Connector, published on 28 Aug 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-2026-81520 and fix it if it is affected.\n\nWhat it is: CVE-2026-81520 is a high-severity denial of service vulnerability in MongoDB BI Connector, published on 28 Aug 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-2026-81520 in the wild and no public exploit code.\n\nAffected product: MongoDB BI Connector. No package-level version data is available, so check the vendor advisory linked from the reference page.\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-2026-81520/ (Markdown: https://insights.sbomify.com/CVE-2026-81520/index.md)","id":"CVE-2026-81520","markdown":"https://insights.sbomify.com/CVE-2026-81520/index.md","name":"CVE-2026-81520","record":{"aliases":["GHSA-435g-jwv8-462q"],"analysis":{"component_type":"server_software","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"MongoDB BI Connector","requires_auth":"none","summary":"Unauthenticated attackers can exhaust connection resources by holding SASL authentication sessions open indefinitely, preventing legitimate users from connecting.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"mongodb","cpe":[{"product":"bi_connector","vendor":"mongodb"}],"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-1088","name":"Synchronous Access of Remote Resource without Timeout"}],"description":"A network-reachable client that has not yet authenticated can hold a MongoDB Connector for BI authentication session open indefinitely by beginning a SASL-based login exchange and then declining to complete it. Because the negotiation loop had no overall time bound and the read from the client had no deadline, each such session retains a worker, a client connection slot, and its associated backend database connections until the process is restarted. Repeated use of this behavior can consume the configured connection capacity and prevent legitimate users from establishing new sessions.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":null,"headline":"MongoDB Connector for BI Unbounded Authentication Negotiation Leading to Connection Exhaustion","id":"CVE-2026-81520","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":1,"next":{"headline":"Cross-database write retargeting via unvalidated dotted database name in Client.BulkWrite in the MongoDB Go Driver","id":"CVE-2026-81521"},"packages":[],"prev":{"headline":"BI Connector Optional Client Certificate Verification Allows Unauthenticated Connections","id":"CVE-2026-81518"},"products":["BI Connector"],"published":"2026-08-28","related":[{"cvss_score":8.7,"headline":"MongoDB Connector for BI Improper Error Handling of Log Write Failures May Cause Loss of SQL Service","id":"CVE-2026-81517","kev_date_added":null,"published":"2026-08-28"},{"cvss_score":8.7,"headline":"BI Connector Optional Client Certificate Verification Allows Unauthenticated Connections","id":"CVE-2026-81518","kev_date_added":null,"published":"2026-08-28"},{"cvss_score":8.5,"headline":"MongoDB Connector for BI Unescaped Object Names in Generated SHOW CREATE Output","id":"CVE-2026-77586","kev_date_added":null,"published":"2026-08-28"},{"cvss_score":8.3,"headline":"MongoDB Connector for BI Improper Error Handling During Schema Sampling May Cause Loss of SQL Service","id":"CVE-2026-81490","kev_date_added":null,"published":"2026-08-28"},{"cvss_score":8.2,"headline":"MongoDB BI Connector Improper Memory Handling During Failed Kerberos Authentication May Cause Process Termination","id":"CVE-2026-75159","kev_date_added":null,"published":"2026-08-27"},{"cvss_score":5.6,"headline":"MongoDB Connector for BI Incomplete Escaping of Stored Metadata in Generated SHOW CREATE Output","id":"CVE-2026-77184","kev_date_added":null,"published":"2026-08-28"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"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":"yes","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-08-31","vendors":["MongoDB"]},"summary":"Unauthenticated attackers can exhaust connection resources by holding SASL authentication sessions open indefinitely, preventing legitimate users from connecting.","url":"https://insights.sbomify.com/CVE-2026-81520/"}