{"id":"CVE-2021-27770","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-27770","generatedAt":"2026-10-27T20:19:12.843Z","title":"The vulnerability was discovered within the “FaviconService”.","description":"The vulnerability was discovered within the “FaviconService”. The service takes a base64-encoded URL which is then requested by the webserver. We assume this service is used by the “meetings”-function where users can specify an external URL where the online meeting will take place.","published":"2022-05-12T22:15:12.000Z","lastModified":"2026-06-17T03:45:26.000Z","status":"Modified","sourceIdentifier":"psirt@hcl.com","cvss":{"version":"3.1","score":8.8,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},"cwe":["CWE-472"],"affected":["hcltech/sametime"],"epss":{"score":0.00736,"percentile":0.54183,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.74%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://support.hcltechsw.com/csm?id=kb_article&sysparm_article=KB0097430","tags":["Vendor Advisory"],"source":"psirt@hcl.com"},{"url":"https://support.hcltechsw.com/csm?id=kb_article&sysparm_article=KB0097430","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-27770","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}