{"id":"CVE-2023-5631","kind":"vulnerability","aliases":["CVE-2023-5631"],"related":[],"title":"Roundcube before 1.4.15, 1.5.x before 1.5.5, and 1.6.x before 1.6.4 allows stored XSS via an HTML e-mail message…","description":"Roundcube Webmail contains a persistent cross-site scripting (XSS) vulnerability that allows a remote attacker to run malicious JavaScript code.\n\nCISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","summary":"Roundcube Webmail, a web-based email client, has a persistent cross-site scripting flaw that lets a remote attacker run malicious JavaScript in a user's browser session. CISA lists it as actively exploited in the wild.","severity":"medium","cvss":6.1,"epss":null,"exploited":true,"exploited_at":"2023-10-26T00:00:00+00:00","products":[{"name":"roundcube webmail","fixed":["1.4.15"],"affected":"< 1.4.15","ecosystem":"vendor"},{"name":"roundcube webmail","fixed":["1.5.5"],"affected":">= 1.5.0, < 1.5.5","ecosystem":"vendor"},{"name":"roundcube webmail","fixed":["1.6.4"],"affected":">= 1.6.0, < 1.6.4","ecosystem":"vendor"},{"name":"debian linux","fixed":[],"affected":"= 10.0","ecosystem":"vendor"},{"name":"debian linux","fixed":[],"affected":"= 11.0","ecosystem":"vendor"},{"name":"debian linux","fixed":[],"affected":"= 12.0","ecosystem":"vendor"},{"name":"fedoraproject fedora","fixed":[],"affected":"= 39","ecosystem":"vendor"},{"name":"Roundcube Webmail","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["exploited","other","roundcube","self-hosted","webmail"],"not_affected_if":["unknown"],"how_to_check":null,"fix":"Apply the vendor mitigation per Roundcube instructions, or discontinue use of the product if mitigations are unavailable (per CISA required action). Specific fixed version: unknown","status":"open","published_at":"2023-10-18T15:15:08+00:00","first_seen_at":"2026-10-23T19:11:51+00:00","triaged_at":"2026-10-23T21:04:22+00:00","updated_at":"2026-10-24T00:09:51+00:00","category":"other","confidence":0.5,"triage":{"at":"2026-10-23T21:04:22Z","model":"claude-haiku-5-5","output":{"fix":"Apply the vendor mitigation per Roundcube instructions, or discontinue use of the product if mitigations are unavailable (per CISA required action). Specific fixed version: unknown","reach":"internet","impact":"medium","summary":"Roundcube Webmail, a web-based email client, has a persistent cross-site scripting flaw that lets a remote attacker run malicious JavaScript in a user's browser session. CISA lists it as actively exploited in the wild.","category":"other","who_cares":["roundcube","self-hosted","webmail"],"confidence":0.5,"needs_auth":"unknown","worst_case":"Attacker runs JavaScript in victim's webmail session, reading or sending mail","analyst_note":"Find affected and fixed Roundcube versions and the vendor advisory for CVE-2023-5631; sources give no version or check method.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["unknown"],"user_interaction":"unknown","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000466,"input_tokens":2826,"output_tokens":366,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2023':24A,27A '-5631':25A,28A '1.4.15':3A '1.5':4A '1.5.5':7A '1.6':9A '1.6.4':12A 'action':114C 'activ':86B 'allow':13A,103C 'appli':115C 'attack':72B,106C 'base':57B 'browser':80B 'cisa':82B,112C 'client':59B 'code':111C 'contain':93C 'cross':64B,97C 'cross-sit':63B,96C 'cve':23A,26A 'debian':35A,37A,39A 'discontinu':121C 'e':20A 'e-mail':19A 'email':58B 'exploit':45B,87B 'fedora':42A 'fedoraproject':41A 'flaw':67B 'host':50B 'html':18A 'instruct':119C 'javascript':75B,110C 'let':69B 'linux':36A,38A,40A 'list':83B 'mail':21A 'malici':74B,109C 'messag':22A 'mitig':116C,127C 'per':117C 'persist':62B,95C 'product':125C 'remot':71B,105C 'requir':113C 'roundcub':1A,47B,52B,91C 'roundcube':29A,31A,33A,43A 'run':73B,108C 'script':66B,99C 'self':49B 'self-host':48B 'session':81B 'site':65B,98C 'store':14A 'unavail':129C 'use':122C 'user':78B 'vendor':118C 'via':16A 'vulner':101C 'web':56B 'web-bas':55B 'webmail':30A,32A,34A,44A,51B,53B,92C 'wild':90B 'x':5A,10A 'xss':15A,100C","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2023-10-18T15:15:08+00:00","kev":{"dateAdded":"2023-10-26","dueDate":"2023-11-16","requiredAction":"Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","knownRansomwareCampaignUse":"Unknown"},"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","cvss_by":"security@eset.com","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2023-5631","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2023-5631","severity":null,"published_at":"2023-10-26T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:51+00:00","fetched_at":"2026-10-25T12:39:23+00:00","note":null},{"source":"nvd","external_id":"CVE-2023-5631","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-5631","severity":null,"published_at":"2023-10-18T15:15:08+00:00","modified_at":"2026-06-17T06:48:58+00:00","first_seen_at":"2026-10-23T22:29:04+00:00","fetched_at":"2026-10-23T22:29:04+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}