CVE-2021-3690 json
Undertow vulnerable to memory exhaustion due to buffer leak
published 2022-07-15 4 y ago modified 2026-06-17 4 mo ago also GHSA-fj7c-vg2v-ccrm , EUVD-2022-6331
- cvss
- 7.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.8%
- EPSS 1.8% chance of exploitation in 30 days, percentile 78%
- public exploits
- 0
- none known
Summary
A flaw was found in Undertow. A buffer leak on the incoming WebSocket PONG message may lead to memory exhaustion. This flaw allows an attacker to cause a denial of service. The highest threat from this vulnerability is availability.
Patch / fix
- maven io.undertow:undertow-core 2.0.40, 2.2.10
- redhat undertow 2.0.40, 2.2.10
- undertow Debian 14 2.2.10-1
debian advisories DEBIAN-CVE-2021-3690
- eap7-netty jboss enterprise application platform 7.4 4.1.63-1.Final_redhat_00001.1.el8eap
- eap7-wildfly jboss enterprise application platform 7.4 7.4.1-2.GA_redhat_00003.1.el8eap
- eap7-undertow jboss enterprise application platform 7.4 2.2.9-2.SP1_redhat_00001.1.el8eap
- eap7-velocity jboss enterprise application platform 7.4 2.3.0-1.redhat_00001.1.el8eap
- eap7-netty-all jboss enterprise application platform 7.4 4.1.63-1.Final_redhat_00001.1.el8eap
- eap7-jakarta-el jboss enterprise application platform 7.4, jboss enterprise application platform 7.3 3.0.3-2.redhat_00006.1.el8eap
- eap7-wildfly-elytron jboss enterprise application platform 7.4 1.15.5-1.Final_redhat_00001.1.el8eap
- eap7-wildfly-modules jboss enterprise application platform 7.4 7.4.1-2.GA_redhat_00003.1.el8eap
red hat advisories RHSA-2025:4226RHSA-2021:3658RHSA-2021:3656RHSA-2021:3466RHSA-2021:3468RHSA-2021:3467
Exploit prediction
1.77% chance of exploitation in the next 30 days, higher than 78% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- issues.redhat.com https://issues.redhat.com/browse/UNDERTOW-1935 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| GitHub | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| maven | io.undertow:undertow-core | <2.0.40 >=2.2.0, <2.2.10 |
2.0.40 2.2.10 |
Affected products
- n/a undertow
Classification
References
-
github.com
/undertow-io/undertow/commit/c7e84a0b7efced38506d7d1dfea5902366973877
web, patch, third-party-advisory
-
issues.redhat.com
/browse/UNDERTOW-1935
web, exploit, issue-tracking, mitigation, vendor-advisory
-
bugzilla.redhat.com
/show_bug.cgi?id=1991299
web, issue-tracking, vendor-advisory
-
access.redhat.com
/security/cve/CVE-2021-3690
web, vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2021-3690
advisory
-
access.redhat.com
/security/cve/cve-2021-3690#cve-cvss-v3
web
-
github.com
/undertow-io/undertow
package
-
mend.io
/vulnerability-database/CVE-2021-3690
web
Sources
- CVE List CVE-2021-3690
- GitHub Advisory GHSA-fj7c-vg2v-ccrm
- NVD CVE-2021-3690
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