{"cve":"CVE-2018-1000518","nvd":{"published":"2018-06-26T16:29:01.243","modified":"2026-06-17T01:32:49.673","status":"Modified","description":"aaugustin websockets version 4 contains a CWE-409: Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in Servers and clients, unless configured with compression=None that can result in Denial of Service by memory exhaustion. This attack appear to be exploitable via Sending a specially crafted frame on an established connection. This vulnerability appears to have been fixed in 5.","cvss_v4":null,"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-400"],"references":["https://github.com/aaugustin/websockets/pull/407","https://github.com/aaugustin/websockets/pull/407"],"products":["websockets_project:websockets"],"source":"nvd","synced_at":"2026-10-19T20:51:47.459859389+00:00"},"epss":{"cve":"CVE-2018-1000518","score":0.01833,"percentile":0.7891,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-6g87-ff9q-v847","url":"https://osv.dev/vulnerability/GHSA-6g87-ff9q-v847","summary":"websockets is vulnerable to denial of service by memory exhaustion","modified":"2024-11-19T18:23:42.891487Z","packages":[{"ecosystem":"PyPI","name":"websockets","purl":"pkg:pypi/websockets","ranges":[">=4.0 <5.0"],"fixed":["5.0"]}]},{"id":"PYSEC-2018-79","url":"https://osv.dev/vulnerability/PYSEC-2018-79","summary":"","modified":"2023-11-08T03:59:38.649508Z","packages":[{"ecosystem":"PyPI","name":"websockets","purl":"pkg:pypi/websockets","ranges":["<5.0"],"fixed":["5.0"]}]}],"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."]}