{"id":"CVE-2023-43809","aliases":["GHSA-mc97-99j4-vm2v","GO-2023-2097"],"url":"https://o3.security/vulnerability/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.","published":"2023-10-04T20:40:41.822Z","modified":"2026-08-12T03:51:31.121593602Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":1,"affectedPackages":[{"ecosystem":"Go","name":"github.com/charmbracelet/soft-serve","fixedVersion":"0.6.2"}],"fix":{"url":"https://github.com/charmbracelet/soft-serve/commit/407c4ec72d1006cee1ff8c1775e5bcc091c2bc89","label":"charmbracelet/soft-serve@407c4ec"},"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"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:31.121593602Z"}}