{"cve":"CVE-2026-21438","nvd":{"published":"2026-02-12T19:15:51.677","modified":"2026-06-17T10:18:40.410","status":"Analyzed","description":"webtransport-go is an implementation of the WebTransport protocol. Prior to 0.10.0, an attacker can cause unbounded memory consumption repeatedly creating and closing many WebTransport streams. Closed streams were not removed from an internal session map, preventing garbage collection of their resources. This vulnerability is fixed in v0.10.0.","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:L","score":5.3},"cwes":["CWE-401","CWE-459"],"references":["https://github.com/quic-go/webtransport-go/releases/tag/v0.10.0","https://github.com/quic-go/webtransport-go/security/advisories/GHSA-2f2x-8mwp-p2gc"],"products":["quic-go:webtransport-go"],"source":"nvd","synced_at":"2026-10-19T22:23:35.260773158+00:00"},"epss":{"cve":"CVE-2026-21438","score":0.00412,"percentile":0.35485,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-2f2x-8mwp-p2gc","url":"https://osv.dev/vulnerability/GHSA-2f2x-8mwp-p2gc","summary":"webtransport-go: Memory Exhaustion Attack due to Missing Cleanup of Streams Map","modified":"2026-09-10T03:50:33.705784889Z","packages":[{"ecosystem":"Go","name":"github.com/quic-go/webtransport-go","purl":"pkg:golang/github.com/quic-go/webtransport-go","ranges":["<0.10.0"],"fixed":["0.10.0"]}]},{"id":"GO-2026-4483","url":"https://osv.dev/vulnerability/GO-2026-4483","summary":"webtransport-go: Memory Exhaustion Attack due to Missing Cleanup of Streams Map in github.com/quic-go/webtransport-go","modified":"2026-02-23T12:43:59.762993Z","packages":[{"ecosystem":"Go","name":"github.com/quic-go/webtransport-go","purl":"pkg:golang/github.com/quic-go/webtransport-go","ranges":["<0.10.0"],"fixed":["0.10.0"]}]}],"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."]}