{"id":"CVE-2026-4873","summary":"connection reuse ignores TLS requirement","details":"A vulnerability exists where a connection requiring TLS incorrectly reuses an\nexisting unencrypted connection from the same connection pool. If an initial\ntransfer is made in clear-text (via IMAP, SMTP, or POP3), a subsequent request\nto that same host bypasses the TLS requirement and instead transmit data\nunencrypted.","aliases":["CURL-CVE-2026-4873"],"modified":"2026-07-08T08:13:39.840791414Z","published":"2026-05-13T08:27:04.538Z","related":["SUSE-SU-2026:1717-1","SUSE-SU-2026:1940-1","SUSE-SU-2026:21452-1","SUSE-SU-2026:22146-1","SUSE-SU-2026:22156-1","SUSE-SU-2026:2703-1","openSUSE-SU-2026:10674-1","openSUSE-SU-2026:20973-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/4xxx/CVE-2026-4873.json","cna_assigner":"curl","unresolved_ranges":[{"extracted_events":[{"introduced":"8.19.0"},{"last_affected":"8.19.0"},{"introduced":"8.18.0"},{"last_affected":"8.18.0"},{"introduced":"8.17.0"},{"last_affected":"8.17.0"},{"introduced":"8.16.0"},{"last_affected":"8.16.0"},{"introduced":"8.15.0"},{"last_affected":"8.15.0"},{"introduced":"8.14.1"},{"last_affected":"8.14.1"},{"introduced":"8.14.0"},{"last_affected":"8.14.0"},{"introduced":"8.13.0"},{"last_affected":"8.13.0"},{"introduced":"8.12.1"},{"last_affected":"8.12.1"},{"introduced":"8.12.0"},{"last_affected":"8.12.0"},{"introduced":"8.11.1"},{"last_affected":"8.11.1"},{"introduced":"8.11.0"},{"last_affected":"8.11.0"},{"introduced":"8.10.1"},{"last_affected":"8.10.1"},{"introduced":"8.10.0"},{"last_affected":"8.10.0"},{"introduced":"8.9.1"},{"last_affected":"8.9.1"},{"introduced":"8.9.0"},{"last_affected":"8.9.0"},{"introduced":"8.8.0"},{"last_affected":"8.8.0"},{"introduced":"8.7.1"},{"last_affected":"8.7.1"},{"introduced":"8.7.0"},{"last_affected":"8.7.0"},{"introduced":"8.6.0"},{"last_affected":"8.6.0"},{"introduced":"8.5.0"},{"last_affected":"8.5.0"},{"introduced":"8.4.0"},{"last_affected":"8.4.0"},{"introduced":"8.3.0"},{"last_affected":"8.3.0"},{"introduced":"8.2.1"},{"last_affected":"8.2.1"},{"introduced":"8.2.0"},{"last_affected":"8.2.0"},{"introduced":"8.1.2"},{"last_affected":"8.1.2"},{"introduced":"8.1.1"},{"last_affected":"8.1.1"},{"introduced":"8.1.0"},{"last_affected":"8.1.0"},{"introduced":"8.0.1"},{"last_affected":"8.0.1"},{"introduced":"8.0.0"},{"last_affected":"8.0.0"},{"introduced":"7.88.1"},{"last_affected":"7.88.1"},{"introduced":"7.88.0"},{"last_affected":"7.88.0"},{"introduced":"7.87.0"},{"last_affected":"7.87.0"},{"introduced":"7.86.0"},{"last_affected":"7.86.0"},{"introduced":"7.85.0"},{"last_affected":"7.85.0"},{"introduced":"7.84.0"},{"last_affected":"7.84.0"},{"introduced":"7.83.1"},{"last_affected":"7.83.1"},{"introduced":"7.83.0"},{"last_affected":"7.83.0"},{"introduced":"7.82.0"},{"last_affected":"7.82.0"},{"introduced":"7.81.0"},{"last_affected":"7.81.0"},{"introduced":"7.80.0"},{"last_affected":"7.80.0"},{"introduced":"7.79.1"},{"last_affected":"7.79.1"},{"introduced":"7.79.0"},{"last_affected":"7.79.0"},{"introduced":"7.78.0"},{"last_affected":"7.78.0"},{"introduced":"7.77.0"},{"last_affected":"7.77.0"},{"introduced":"7.76.1"},{"last_affected":"7.76.1"},{"introduced":"7.76.0"},{"last_affected":"7.76.0"},{"introduced":"7.75.0"},{"last_affected":"7.75.0"},{"introduced":"7.74.0"},{"last_affected":"7.74.0"},{"introduced":"7.73.0"},{"last_affected":"7.73.0"},{"introduced":"7.72.0"},{"last_affected":"7.72.0"},{"introduced":"7.71.1"},{"last_affected":"7.71.1"},{"introduced":"7.71.0"},{"last_affected":"7.71.0"},{"introduced":"7.70.0"},{"last_affected":"7.70.0"},{"introduced":"7.69.1"},{"last_affected":"7.69.1"},{"introduced":"7.69.0"},{"last_affected":"7.69.0"},{"introduced":"7.68.0"},{"last_affected":"7.68.0"},{"introduced":"7.67.0"},{"last_affected":"7.67.0"},{"introduced":"7.66.0"},{"last_affected":"7.66.0"},{"introduced":"7.65.3"},{"last_affected":"7.65.3"},{"introduced":"7.65.2"},{"last_affected":"7.65.2"},{"introduced":"7.65.1"},{"last_affected":"7.65.1"},{"introduced":"7.65.0"},{"last_affected":"7.65.0"},{"introduced":"7.64.1"},{"last_affected":"7.64.1"},{"introduced":"7.64.0"},{"last_affected":"7.64.0"},{"introduced":"7.63.0"},{"last_affected":"7.63.0"},{"introduced":"7.62.0"},{"last_affected":"7.62.0"},{"introduced":"7.61.1"},{"last_affected":"7.61.1"},{"introduced":"7.61.0"},{"last_affected":"7.61.0"},{"introduced":"7.60.0"},{"last_affected":"7.60.0"},{"introduced":"7.59.0"},{"last_affected":"7.59.0"},{"introduced":"7.58.0"},{"last_affected":"7.58.0"},{"introduced":"7.57.0"},{"last_affected":"7.57.0"},{"introduced":"7.56.1"},{"last_affected":"7.56.1"},{"introduced":"7.56.0"},{"last_affected":"7.56.0"},{"introduced":"7.55.1"},{"last_affected":"7.55.1"},{"introduced":"7.55.0"},{"last_affected":"7.55.0"},{"introduced":"7.54.1"},{"last_affected":"7.54.1"},{"introduced":"7.54.0"},{"last_affected":"7.54.0"},{"introduced":"7.53.1"},{"last_affected":"7.53.1"},{"introduced":"7.53.0"},{"last_affected":"7.53.0"},{"introduced":"7.52.1"},{"last_affected":"7.52.1"},{"introduced":"7.52.0"},{"last_affected":"7.52.0"},{"introduced":"7.51.0"},{"last_affected":"7.51.0"},{"introduced":"7.50.3"},{"last_affected":"7.50.3"},{"introduced":"7.50.2"},{"last_affected":"7.50.2"},{"introduced":"7.50.1"},{"last_affected":"7.50.1"},{"introduced":"7.50.0"},{"last_affected":"7.50.0"},{"introduced":"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