Vulnerability · Published Apr 23, 2021 · Assigned by Vaadin

CVE-2021-31404Timing side channel vulnerability in UIDL request handler in Vaadin 10, 11-14, and 15-18

Medium 4.0

In plain English

A medium-severity security flaw in flow-server from Vaadin. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 11% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.0Medium

Exploit odds (30 days)0.2%top 88.7% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official description

Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:flow-server versions 1.0.0 through 1.0.13 (Vaadin 10.0.0 through 10.0.16), 1.1.0 prior to 2.0.0 (Vaadin 11 prior to 14), 2.0.0 through 2.4.6 (Vaadin 14.0.0 through 14.4.6), 3.0.0 prior to 5.0.0 (Vaadin 15 prior to 18), and 5.0.0 through 5.0.2 (Vaadin 18.0.0 through 18.0.5) allows attacker to guess a security token via timing attack.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Maven	com.vaadin:flow-server	1.0.14	GHSA-xwg3-qrcg-w9x6
Maven	com.vaadin:flow-server	2.4.7	GHSA-xwg3-qrcg-w9x6
Maven	com.vaadin:flow-server	5.0.3	GHSA-xwg3-qrcg-w9x6

Affected products (as reported)

Vendor	Product	Versions
Vaadin	Vaadin	10.0.0 – before *
Vaadin	flow-server	1.0.0 – before *

Weakness: CWE-208 · Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

References

https://vaadin.com/security/cve-2021-31404 x_refsource_MISC
https://github.com/vaadin/flow/pull/9875 x_refsource_MISC