Home/CVE/A flaw was found in Undertow that tripped the client-side invocation timeout with certain calls made over HTTP2. This fl
CVE

CVE-2021-3859

A flaw was found in Undertow that tripped the client-side invocation timeout with certain calls made over HTTP2. This fl

A flaw was found in Undertow that tripped the client-side invocation timeout with certain calls made over HTTP2. This flaw allows an attacker to carry out denial of service attacks.

HIGH · CVSS 7.5 EPSS 0.00318
Schedule remediation
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-214Invocation of Process Using Visible Sensitive Information
CWE-668Exposure of Resource to Wrong Sphere
▤

Affected Products & Versions

6
redhat jboss enterprise application platformall versions
redhat single sign-onall versions
redhat undertow< 2.2.15
netapp cloud secure agentall versions
netapp oncommand insightall versions
netapp oncommand workflow automationall versions
▤

Affected Packages

1
Language-ecosystem packages (from OSV) tied to this CVE, with the version that fixes it - the dependency-level detail NVD doesn’t carry.
Maven io.undertow:undertow-core HIGH fixed in 2.2.15
▣

Scoring & Timeline

7.5
HIGH · CVSS v3.1 · secalert@redhat.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD26 Aug 2022 · 04:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
⚑

Vendor Advisories

16
rhsaRHSA-2024:10207Critical
rhsaRHSA-2025:4226Important
rhsaRHSA-2022:5532Important
rhsaRHSA-2022:0409Important
rhsaRHSA-2022:0408Important
🔗

References & Sources

6
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://access.redhat.com/security/cve/CVE-2021-3859Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2010378Issue TrackingVendor Advisory
https://github.com/undertow-io/undertow/commit/e43f0ada3f4da6e8579e0020cec3cb1a81e487c2PatchThird Party Advisory
https://github.com/undertow-io/undertow/pull/1296Third Party Advisory
https://issues.redhat.com/browse/UNDERTOW-1979Issue TrackingPatchVendor Advisory
https://security.netapp.com/advisory/ntap-20221201-0004/Third Party Advisory
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