{"cve":"CVE-2026-54275","nvd":{"published":"2026-06-22T18:16:46.010","modified":"2026-10-25T23:10:00.167","status":"Analyzed","description":"AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, the server_hostname TLS SNI check can be bypassed when an existing connection is reused. If an application makes multiple requests to the same domain, but with different per-request server_hostname parameters, then the later calls may succeed by reusing the existing connection when they should have been rejected due to the TLS SNI check. This vulnerability is fixed in 3.14.1.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U","score":2.7},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-297"],"references":["https://github.com/aio-libs/aiohttp/security/advisories/GHSA-4m7w-qmgq-4wj5"],"products":["aiohttp:aiohttp"],"source":"nvd","synced_at":"2026-10-25T23:44:33.281319194+00:00"},"epss":{"cve":"CVE-2026-54275","score":0.0047,"percentile":0.4042,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-4m7w-qmgq-4wj5","url":"https://osv.dev/vulnerability/GHSA-4m7w-qmgq-4wj5","summary":"aiohttp: TLS Server Hostname Override Is Ignored When Reusing HTTPS Connections","modified":"2026-09-10T03:50:48.205198252Z","packages":[{"ecosystem":"PyPI","name":"aiohttp","purl":"pkg:pypi/aiohttp","ranges":["<3.14.1"],"fixed":["3.14.1"]}]},{"id":"PYSEC-2026-237","url":"https://osv.dev/vulnerability/PYSEC-2026-237","summary":"","modified":"2026-06-27T11:15:05.309750506Z","packages":[{"ecosystem":"PyPI","name":"aiohttp","purl":"pkg:pypi/aiohttp","ranges":["<3.14.1"],"fixed":["3.14.1"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}