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CVE

CVE-2020-27782

A flaw was found in the Undertow AJP connector. Malicious requests and abrupt connection closes could be triggered by an

A flaw was found in the Undertow AJP connector. Malicious requests and abrupt connection closes could be triggered by an attacker using query strings with non-RFC compliant characters resulting in a denial of service. The highest threat from this vulnerability is to system availability.

This affects Undertow 2.1.5.SP1, 2.0.33.SP2, and 2.2.3.SP1.

HIGH · CVSS 7.5 EPSS 0.00182
Schedule remediation
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-400Uncontrolled Resource Consumption
▤

Affected Products & Versions

3
redhat jboss fuseall versions
redhat openshift application runtimesall versions
redhat undertowall 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 2.1.5
▣

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 NVD23 Feb 2021 · 07:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
⚑

Vendor Advisories

11
rhsaRHSA-2025:9582Moderate
rhsaRHSA-2021:5134Critical
rhsaRHSA-2021:3425Important
rhsaRHSA-2021:3205Moderate
rhsaRHSA-2021:3207Important
🔗

References & Sources

1
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://bugzilla.redhat.com/show_bug.cgi?id=1901304Issue TrackingVendor Advisory
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