CVE-2021-3694: Cross-site Scripting (XSS) - Reflected in ledgersmb/ledgersmb

Severity: critical (CVSS 9.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-08-23 · updated 2026-06-17
Weakness: CWE-79

Description

LedgerSMB does not sufficiently HTML-encode error messages sent to the browser. By sending a specially crafted URL to an authenticated user, this flaw can be abused for remote code execution and information disclosure.

Affected products

Debian Linux: 10.0, 11.0
ledgersmb/ledgersmb: from 1.1.0 through 1.1.12; from 1.2.0 through 1.2.26; from 1.3.0 through 1.3.47; from 1.4.0 through 1.4.42; from 1.5.0 through 1.5.30; from 1.6.0 through 1.6.33

References

https://github.com/ledgersmb/ledgersmb/commit/98fa476d46a4a7e5e9492ed69b4fa190be5547fc
https://huntr.dev/bounties/ef7f4cf7-3a81-4516-b261-f5b6ac21430c
https://ledgersmb.org/cve-2021-3694-cross-site-scripting
https://www.debian.org/security/2021/dsa-4962
https://github.com/ledgersmb/ledgersmb/commit/98fa476d46a4a7e5e9492ed69b4fa190be5547fc
https://huntr.dev/bounties/ef7f4cf7-3a81-4516-b261-f5b6ac21430c
https://ledgersmb.org/cve-2021-3694-cross-site-scripting
https://www.debian.org/security/2021/dsa-4962

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