Loading vulnerability…
CVE-2023-43770 is a cross-site scripting vulnerability in Roundcube Webmail affecting versions before 1.4.14, 1.5.x before 1.5.4, and 1.6.x before 1.6.3. The flaw is triggered when Roundcube processes crafted links in text/plain email messages due to unsafe behavior in rcube_string_replacer.php. A specially crafted email can cause attacker-controlled JavaScript to execute in the context of the victim’s authenticated Roundcube webmail session when the message is viewed. The issue has been used in espionage campaigns as a near-zero-interaction or zero-click webmail exploit to steal mailbox data and session-accessible secrets.
Mallory correlates every CVE against your assets, your vendors, and active adversary campaigns. Know which vulnerabilities matter for you, not just which ones are loud.
What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.
What an attacker gets, and what they’ve been doing with it.
If you can’t patch tonight, do this now.
Patch, then assume compromise.
1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos.
This repository provides a proof-of-concept (POC) exploit for CVE-2023-43770, a stored cross-site scripting (XSS) vulnerability in Roundcube Webmail (versions before 1.4.14, 1.5.x before 1.5.4, and 1.6.x before 1.6.3). The exploit consists of a single Python script (cve-2023-43770.py) that sends a specially crafted plain text email containing a malicious JavaScript payload to a target user. The script requires the attacker to provide sender email credentials and the recipient's email address, and it uses SMTP (defaulting to smtp.gmail.com:587) to deliver the payload. When the victim views the email in a vulnerable Roundcube instance, the JavaScript executes, demonstrating the XSS vulnerability. The repository also includes a README.md with usage instructions, references, and a disclaimer. No detection or scanning functionality is present; the code is strictly a POC for educational and testing purposes.
Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.
Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.
17 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A Roundcube vulnerability cited as one of the webmail flaws exploited by TA458 in Operation RoundPress.
Cross-site scripting vulnerability in Roundcube Webmail used by APT28 as an updated initial access vector via crafted links in text/plain email.
A Roundcube webmail persistent cross-site scripting vulnerability exploited by TA458 in webmail compromise campaigns.
A specific Roundcube vulnerability referenced as the key flaw to patch in connection with FancyBear's webmail exploitation campaign and XSS-based compromise activity.
Query your assets running an affected version, and investigate the blast radius.
Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.