{"id":"CVE-2023-43809","summary":"Soft Serve Public Key Authentication Bypass Vulnerability when Keyboard-Interactive SSH Authentication is Enabled","details":"Soft Serve is a self-hostable Git server for the command line. Prior to version 0.6.2, a security vulnerability in Soft Serve could allow an unauthenticated, remote attacker to bypass public key authentication when keyboard-interactive SSH authentication is active, through the `allow-keyless` setting, and the public key requires additional client-side verification for example using FIDO2 or GPG. This is due to insufficient validation procedures of the public key step during SSH request handshake, granting unauthorized access if the keyboard-interaction mode is utilized. An attacker could exploit this vulnerability by presenting manipulated SSH requests using keyboard-interactive authentication mode. This could potentially result in unauthorized access to the Soft Serve. Users should upgrade to the latest Soft Serve version `v0.6.2` to receive the patch for this issue. To workaround this vulnerability without upgrading, users can temporarily disable Keyboard-Interactive SSH Authentication using the `allow-keyless` setting.","aliases":["GHSA-mc97-99j4-vm2v","GO-2023-2097"],"modified":"2026-04-10T05:03:56.252166Z","published":"2023-10-04T20:40:41.822Z","database_specific":{"cwe_ids":["CWE-287"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/43xxx/CVE-2023-43809.json","cna_assigner":"GitHub_M"},"references":[{"type":"WEB","url":"https://github.com/charmbracelet/soft-serve/releases/tag/v0.6.2"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/43xxx/CVE-2023-43809.json"},{"type":"ADVISORY","url":"https://github.com/charmbracelet/soft-serve/security/advisories/GHSA-mc97-99j4-vm2v"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-43809"},{"type":"REPORT","url":"https://github.com/charmbracelet/soft-serve/issues/389"},{"type":"FIX","url":"https://github.com/charmbracelet/soft-serve/commit/407c4ec72d1006cee1ff8c1775e5bcc091c2bc89"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/charmbracelet/soft-serve","events":[{"introduced":"0"},{"fixed":"6f0a418a36db7ee867ebcf775558fbe0159d96a6"}]}],"versions":["v0.1.0","v0.1.1","v0.1.2","v0.1.3","v0.2.0","v0.2.1","v0.2.2","v0.2.3","v0.3.0","v0.3.1","v0.3.2","v0.4.0","v0.4.1","v0.4.2","v0.4.3","v0.4.4","v0.4.5","v0.4.6","v0.4.7","v0.5.0","v0.5.1","v0.5.2","v0.5.3","v0.5.4","v0.6.0","v0.6.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-43809.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"}]}