{"cve":"CVE-2026-35515","nvd":{"published":"2026-04-07T16:16:27.773","modified":"2026-10-26T21:10:00.170","status":"Analyzed","description":"Nest is a framework for building scalable Node.js server-side applications. Prior to 11.1.18, SseStream._transform() interpolates message.type and message.id directly into Server-Sent Events text protocol output without sanitizing newline characters (\\r, \\n). Since the SSE protocol treats both \\r and \\n as field delimiters and \\n\\n as event boundaries, an attacker who can influence these fields through upstream data sources can inject arbitrary SSE events, spoof event types, and corrupt reconnection state. This vulnerability is fixed in 11.1.18.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:L/SA:N","score":6.3},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:L","score":6.1},"cwes":["CWE-74"],"references":["https://github.com/nestjs/nest/security/advisories/GHSA-36xv-jgw5-4q75"],"products":["nestjs:nest"],"source":"nvd","synced_at":"2026-10-26T21:38:48.864438205+00:00"},"epss":{"cve":"CVE-2026-35515","score":0.00234,"percentile":0.14218,"date":"2026-10-26"},"kev":null,"osv":[{"id":"GHSA-36xv-jgw5-4q75","url":"https://osv.dev/vulnerability/GHSA-36xv-jgw5-4q75","summary":"@nestjs/core Improperly Neutralizes Special Elements in Output Used by a Downstream Component ('Injection')","modified":"2026-09-10T03:50:42.305999581Z","packages":[{"ecosystem":"npm","name":"@nestjs/core","purl":"pkg:npm/%40nestjs/core","ranges":["<11.1.18"],"fixed":["11.1.18"]}]}],"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."]}