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

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.

Published: 2021-08-23 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-3694 is rated Moderate Risk (49.4/100): CVSS High severity, with low exploitation likelihood (EPSS 0.25%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-3694

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-12-13 0.62% 0.25% -0.37%
2 2025-11-21 0.80% 0.62% -0.18%
3 2025-11-18 — 0.80% —

Full EPSS history (21 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-3694

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.2 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 4.7 [email protected]
9.6 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 6.0 [email protected]
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 6.4 [email protected]

Weakness enumeration for CVE-2021-3694

OS Trackers for CVE-2021-3694

vendor priority summary link
debian not yet assigned CVE-2021-3694 not yet assigned priority: Debian including 1 source packages (ledgersmb), 2 status rows across 2 suites (bookworm, bullseye): resolved 2. https://security-tracker.debian.org/tracker/CVE-2021-3694
ubuntu medium CVE-2021-3694 medium priority: Ubuntu including 1 source packages (ledgersmb), 14 status rows across 14 suites (bionic, focal, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, trusty, upstream, xenial): not-affected 5, ignored 4, released 4, DNE 1. https://ubuntu.com/security/CVE-2021-3694

Affected software / configurations for CVE-2021-3694

Vendor Product Version Raw CPE
ledgersmb ledgersmb >= 1.1.0, <= 1.1.12 cpe:2.3:a:ledgersmb:ledgersmb:*:*:*:*:*:*:*:*
ledgersmb ledgersmb >= 1.2.0, <= 1.2.26 cpe:2.3:a:ledgersmb:ledgersmb:*:*:*:*:*:*:*:*
ledgersmb ledgersmb >= 1.3.0, <= 1.3.47 cpe:2.3:a:ledgersmb:ledgersmb:*:*:*:*:*:*:*:*
ledgersmb ledgersmb >= 1.4.0, <= 1.4.42 cpe:2.3:a:ledgersmb:ledgersmb:*:*:*:*:*:*:*:*
ledgersmb ledgersmb >= 1.5.0, <= 1.5.30 cpe:2.3:a:ledgersmb:ledgersmb:*:*:*:*:*:*:*:*
ledgersmb ledgersmb >= 1.6.0, <= 1.6.33 cpe:2.3:a:ledgersmb:ledgersmb:*:*:*:*:*:*:*:*
ledgersmb ledgersmb >= 1.7.0, <= 1.7.32 cpe:2.3:a:ledgersmb:ledgersmb:*:*:*:*:*:*:*:*
ledgersmb ledgersmb >= 1.8.0, <= 1.8.17 cpe:2.3:a:ledgersmb:ledgersmb:*:*:*:*:*:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
debian debian_linux 11.0 cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

References for CVE-2021-3694

cvelogic Threat Intelligence