CVE-2021-31412 | Possible route enumeration in production mode via RouteNotFoundError view in Vaadin 10, 11-14, and 15-19

Improper sanitization of path in default RouteNotFoundError view in com.vaadin:flow-server versions 1.0.0 through 1.0.14 (Vaadin 10.0.0 through 10.0.18), 1.1.0 prior to 2.0.0 (Vaadin 11 prior to 14), 2.0.0 through 2.6.1 (Vaadin 14.0.0 through 14.6.1), and 3.0.0 through 6.0.9 (Vaadin 15.0.0 through 19.0.8) allows network attacker to enumerate all available routes via crafted HTTP request when application is running in production mode and no custom handler for NotFoundException is provided.

Published: 2021-06-24 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-31412 is rated Moderate Risk (45.3/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.32%). 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-2021-31412

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 2026-06-15 0.69% 1.32% +0.63%
2 2025-12-28 0.91% 0.69% -0.23%
3 2025-12-27 — 0.91% —

Full EPSS history (14 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-31412

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 [email protected]
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:N/A:N 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:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2021-31412

GitHub Security Advisory for CVE-2021-31412

GHSA-qrg9-f472-qwfm · Severity: medium · Ecosystem: maven — Possible route enumeration in production mode via RouteNotFoundError view in Vaadin 10, 11-14, and 15-19

Affected software / configurations for CVE-2021-31412

Vendor Product Version Raw CPE
vaadin flow >= 1.0.0, <= 1.0.14 cpe:2.3:a:vaadin:flow:*:*:*:*:*:*:*:*
vaadin flow >= 1.1.0, <= 1.4.0 cpe:2.3:a:vaadin:flow:*:*:*:*:*:*:*:*
vaadin flow >= 2.0.0, <= 2.6.1 cpe:2.3:a:vaadin:flow:*:*:*:*:*:*:*:*
vaadin flow >= 3.0.0, <= 5.0.0 cpe:2.3:a:vaadin:flow:*:*:*:*:*:*:*:*
vaadin flow >= 6.0.0, <= 6.0.9 cpe:2.3:a:vaadin:flow:*:*:*:*:*:*:*:*
vaadin vaadin >= 10.0.0, <= 10.0.18 cpe:2.3:a:vaadin:vaadin:*:*:*:*:*:*:*:*
vaadin vaadin >= 11.0.0, <= 13.0.0 cpe:2.3:a:vaadin:vaadin:*:*:*:*:*:*:*:*
vaadin vaadin >= 14.0.0, <= 14.6.1 cpe:2.3:a:vaadin:vaadin:*:*:*:*:*:*:*:*
vaadin vaadin >= 15.0.0, <= 18.0.0 cpe:2.3:a:vaadin:vaadin:*:*:*:*:*:*:*:*
vaadin vaadin >= 19.0.0, <= 19.0.8 cpe:2.3:a:vaadin:vaadin:*:*:*:*:*:*:*:*

References for CVE-2021-31412

cvelogic Threat Intelligence