CVE-2021-3693 Cross-site Scripting (XSS) - DOM in ledgersmb/ledgersmb

What is CVE-2021-3693?

CVE-2021-3693 is a high-severity cross-site scripting vulnerability in Debian Debian Linux, published on 23 Aug 2021. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

LedgerSMB does not check the origin of HTML fragments merged into the browser's DOM. By sending a specially crafted URL to an authenticated user, this flaw can be abused for remote code execution and information disclosure.

Weakness: CWE-79

Which versions are affected by CVE-2021-3693?

It affects 2 products.

Products include Debian Debian Linux, Ledgersmb Ledgersmb.

How do I fix CVE-2021-3693?

Apply the vendor's patch.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2021-3693 being exploited?

There is no known exploitation of CVE-2021-3693 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2021-3693, GHSA-x27f-prq2-qwh6, UBUNTU-CVE-2021-3693.