{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2023-28623 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2023-28623 yet. Limit exposure of the affected software until one is available.","what":"CVE-2023-28623 is a medium-severity authentication bypass vulnerability in zulip, published on 19 May 2023. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2023-28623 and fix it if it is affected.\n\nWhat it is: CVE-2023-28623 is a medium-severity authentication bypass vulnerability in zulip, published on 19 May 2023. 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-2023-28623 in the wild and no public exploit code.\n\nAffected product: zulip. 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-2023-28623/ (Markdown: https://insights.sbomify.com/CVE-2023-28623/index.md)","id":"CVE-2023-28623","markdown":"https://insights.sbomify.com/CVE-2023-28623/index.md","name":"CVE-2023-28623","record":{"aliases":["GHSA-7p62-pjwg-56rv"],"analysis":{"component_type":"web_application","fix_type":"upgrade","impacts":["account_takeover"],"network_reachable":"yes","non_default_config":true,"product_category":"Zulip team collaboration","requires_auth":"none","summary":"Attackers can register unauthorized accounts in Zulip when specific LDAP and external authentication backends are enabled without invitation requirements.","user_interaction":"not_required","vuln_class":"auth_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"zulip","vendor":"zulip"}],"cvss":{"score":6.5,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-862","name":"Missing Authorization"},{"id":"CWE-285","name":"Improper Authorization"}],"description":"Zulip is an open-source team collaboration tool with unique topic-based threading. In the event that 1: `ZulipLDAPAuthBackend` and an external authentication backend (any aside of `ZulipLDAPAuthBackend` and `EmailAuthBackend`) are the only ones enabled in `AUTHENTICATION_BACKENDS` in `/etc/zulip/settings.py` and 2: The organization permissions don't require invitations to join. An attacker can create a new account in the organization with an arbitrary email address in their control that's not in the organization's LDAP directory. The impact is limited to installations which have this specific combination of authentication backends as described above in addition to having `Invitations are required for joining this organization` organization permission disabled. This issue has been addressed in version 6.2. Users are advised to upgrade. Users unable to upgrade may enable the `Invitations are required for joining this organization` organization permission to prevent this issue.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":false,"headline":"Unauthorized user can register an account in specific configurations in Zulip","id":"CVE-2023-28623","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"auth_bypass","year":"2023"},"n_packages":0,"n_references":2,"next":{"headline":"mod_auth_openidc core dump when OIDCStripCookies is set and an empty Cookie header is supplied","id":"CVE-2023-28625"},"packages":[],"prev":{"headline":"WordPress Easy Slider Revolution Plugin \u003c= 1.0.0 is vulnerable to Cross Site Scripting (XSS)","id":"CVE-2023-28622"},"products":["zulip"],"published":"2023-05-19","related":[{"cvss_score":8.6,"headline":"RabbitMQ exposes ports with weak default secrets in Zulip Server","id":"CVE-2021-43799","kev_date_added":null,"published":"2022-01-25"},{"cvss_score":8,"headline":"Crafted link in Zulip message can cause disclosure of credentials","id":"CVE-2022-35962","kev_date_added":null,"published":"2022-08-29"},{"cvss_score":7.5,"headline":"Auth bypass in zulip","id":"CVE-2016-4427","kev_date_added":null,"published":"2022-07-28"},{"cvss_score":6.8,"headline":"Cross-site Scripting (XSS) - Stored in zulip/zulip","id":"CVE-2021-3866","kev_date_added":null,"published":"2022-01-20"},{"cvss_score":6.5,"headline":"Ineffective expiration validation for invitation links in Zulip","id":"CVE-2021-43791","kev_date_added":null,"published":"2021-12-02"},{"cvss_score":6.1,"headline":"Zulip: Path Traversal in Import","id":"CVE-2026-26058","kev_date_added":null,"published":"2026-04-03"}],"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":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2025-02-12","vendors":["zulip"]},"summary":"Attackers can register unauthorized accounts in Zulip when specific LDAP and external authentication backends are enabled without invitation requirements.","url":"https://insights.sbomify.com/CVE-2023-28623/"}