{"id":"CVE-2026-5773","title":"libcurl might in some circumstances reuse the wrong connection for SMB(S)\ntransfers.\n\nlibcurl features a pool of recent connections so that subsequent requests can\nreuse an existing connection to avoid overhead.\n\nWhen reusing a connectio…","summary":"libcurl might in some circumstances reuse the wrong connection for SMB(S)\ntransfers.\n\nlibcurl features a pool of recent connections so that subsequent requests can\nreuse an existing connection to avoid overhead.\n\nWhen reusing a connectio…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","cwe":["CWE-488","CWE-918"],"vendor":"haxx","product":"curl","affected":["curl >= 7.40.0, < 8.20.0"],"patched":["curl 8.20.0"],"published":"2026-05-13","updated":"2026-09-15","sourceUpdated":"2026-09-15T07:16:28.820","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-5773","references":[{"url":"https://curl.se/docs/CVE-2026-5773.html","label":"2499f714-1537-4658-8207-48ae4bb9eae9"},{"url":"https://curl.se/docs/CVE-2026-5773.json","label":"2499f714-1537-4658-8207-48ae4bb9eae9"},{"url":"https://hackerone.com/reports/3650689","label":"2499f714-1537-4658-8207-48ae4bb9eae9"},{"url":"http://www.openwall.com/lists/oss-security/2026/04/29/9","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://hackerone.com/reports/3650689","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"tags":["nvd","cve.org","exploit-available"],"exploitAvailable":true,"ssvc":{"exploitation":"poc","automatable":"yes","technicalImpact":"partial","timestamp":"2026-05-13T17:45:00.901945Z"},"epss":0.00618,"epssPercentile":0.47948,"ingestedAt":"2026-09-15T07:33:29.265Z","slug":"CVE-2026-5773","body":"## Overview\n\nlibcurl might in some circumstances reuse the wrong connection for SMB(S)\ntransfers.\n\nlibcurl features a pool of recent connections so that subsequent requests can\nreuse an existing connection to avoid overhead.\n\nWhen reusing a connection a range of criteria must be met. Due to a logical\nerror in the code, a network transfer operation that was requested by an\napplication could wrongfully reuse an existing SMB connection to the same\nserver that was using a different \"share\" than the new subsequent transfer\nshould.\n\nThis could in unlucky situations lead to the download of the wrong file or the\nupload of a file to the wrong place. When this happens, the same credentials\nare used and the server name is the same.\n\n## Affected\n\n- `curl >= 7.40.0, < 8.20.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `curl 8.20.0`","depth":"midnight","depthScore":53,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[]}