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EUVD-2026-362254
European Vulnerability Database identifier assigned by ENISAReserved
2026-10-02 08:31
Assigner
ENISA
Alias of
a CVE record, shown under related vulnerabilities.
This identifier carries no description, severity or references of its own:
they belong to that CVE.
{
"assigner": "ENISA",
"date_reserved": "2026-10-02T08:31:24.339441+00:00",
"id": "EUVD-2026-362254"
}
CVE-2026-44390 (GCVE-0-2026-44390)
Vulnerability from cvelistv5 – Published: 2026-05-20 09:21 – Updated: 2026-09-01 12:04
VLAI
EPSS
VEX
Title
Unbounded name compression in certain cases causes degradation of service
Summary
NLnet Labs Unbound up to and including version 1.25.0 has a vulnerability when handling replies with very large RRsets that Unbound needs to perform name compression for. Malicious upstream responses with very large RRsets with records that don't share a suffix above the root can cause Unbound to spend a considerable time applying name compression to downstream replies. This can lead to degraded performance and eventually denial of service in well orchestrated attacks. An adversary can exploit the vulnerability by querying Unbound for the specially crafted contents of a malicious zone with very large RRsets. Before Unbound replies to the query it will try to apply name compression which was an unbounded operation that could lock the CPU until the whole packet was complete. A compression limit was introduced in 1.21.1 for this but it didn't account for the case where records would not share any suffix above the root. That causes Unbound to go in a different code path because of the compression tree lookup failure and eventually not increment the compression counter for those operations. Unbound 1.25.1 contains a patch with a fix that increments the compression counter regardless of the compression tree lookup. This is a complement fix to CVE-2024-8508.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-20 12:55 UTC
CWE
Assigner
References
8 references
| URL | Tags |
|---|---|
| https://www.nlnetlabs.nl/downloads/unbound/CVE-20… | vendor-advisory |
| https://access.redhat.com/security/cve/CVE-2026-44390 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2480130 | issue-trackingx_refsource_REDHAT |
| https://security.access.redhat.com/data/csaf/v2/v… | x_sadp-csaf-vex |
| https://access.redhat.com/errata/RHSA-2026:36320 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:37282 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:36777 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:24013 | vendor-advisoryx_refsource_REDHAT |
Impacted products
8 products
| Vendor | Product | Version | |
|---|---|---|---|
| NLnet Labs | Unbound |
Affected:
0 , < 1.25.1
(semver)
|
|
| Red Hat | Red Hat Enterprise Linux 10 |
Unaffected:
0:1.24.2-7.el10_2.2 , < *
(rpm)
cpe:/o:redhat:enterprise_linux:10.2 |
|
| Red Hat | Red Hat Enterprise Linux 8 |
Unaffected:
0:1.16.2-5.12.el8_10 , < *
(rpm)
cpe:/a:redhat:enterprise_linux:8 |
|
| Red Hat | Red Hat Enterprise Linux 9 |
Unaffected:
0:1.24.2-3.el9_8.2 , < *
(rpm)
cpe:/a:redhat:enterprise_linux:9 |
|
| Red Hat | Red Hat Hardened Images |
Unaffected:
1.25.1-2.hum1 , < *
(rpm)
cpe:/a:redhat:hummingbird:1 |
|
| Red Hat | Red Hat Enterprise Linux 6 |
cpe:/o:redhat:enterprise_linux:6
|
|
| Red Hat | Red Hat Enterprise Linux 7 |
cpe:/o:redhat:enterprise_linux:7
|
|
| Red Hat | Red Hat OpenShift Container Platform 4 |
cpe:/a:redhat:openshift:4
|
Date Public
2026-05-20 00:00
Credits
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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- Confirmed: The vulnerability has been validated from an analyst's perspective.
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- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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- Not confirmed: The user expressed doubt about the validity of the vulnerability.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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