Cyber Resilience

CVE-2021-31403

Medium

Published: 23 April 2021

Published
23 April 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 4.0 CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
EPSS Score 0.0013 31.8th percentile
Risk Priority 8 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-31403 is a medium-severity Observable Timing Discrepancy (CWE-208) vulnerability in Vaadin Vaadin. Its CVSS base score is 4.0 (Medium).

Operationally, ranked at the 31.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:vaadin-server versions 7.0.0 through 7.7.23 (Vaadin 7.0.0 through 7.7.23), and 8.0.0 through 8.12.2 (Vaadin 8.0.0 through 8.12.2) allows attacker to guess a security token via timing attack

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

vaadin
vaadin
7.0.0 — 7.7.24 · 8.0.0 — 8.12.3

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-203 CWE-208

Misdirection can normalize or falsify responses to eliminate observable discrepancies that aid reconnaissance.

addresses: CWE-208 CWE-203

Observable timing discrepancies are a primary mechanism for constructing covert timing channels; analysis identifies and bounds them, limiting exploitation.

addresses: CWE-203

Prevents attackers from using observable differences in error responses to infer internal system details or state.

References