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CVE-2026-4890 (GCVE-0-2026-4890)

Vulnerability from cvelistv5 – Published: 2026-05-11 16:47 – Updated: 2026-09-01 12:05
VLAI
Title
CVE-2026-4890
Summary
A Denial of Service (DoS) vulnerability in the DNSSEC validation of dnsmasq allows remote attackers to cause a denial of service via a crafted DNS packet.
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-11 18:28 UTC
CWE
  • CWE-835 - Loop with Unreachable Termination
  • CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Impacted products
Vendor Product Version CPE status
dnsmasq dnsmasq Affected: 0 , < 2.92rel2 (custom)
guessed Create a notification for this product.
Red Hat Red Hat Enterprise Linux 10 Unaffected: 0:2.90-7.el10_2 , < * (rpm)
    cpe:/o:redhat:enterprise_linux:10.2
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 8 Unaffected: 0:2.79-36.el8_10 , < * (rpm)
    cpe:/a:redhat:enterprise_linux:8
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 9 Unaffected: 0:2.85-18.el9_8.1 , < * (rpm)
    cpe:/a:redhat:enterprise_linux:9
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support Unaffected: 0:2.85-17.el9_6.1 , < * (rpm)
    cpe:/a:redhat:rhel_eus:9.6
Create a notification for this product.
Red Hat Red Hat OpenShift Container Platform 4.19 Unaffected: 4.19.9.6.202607151909-0 , < * (rpm)
    cpe:/a:redhat:openshift:4.19::el9
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:enterprise_linux:6
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
Create a notification for this product.
Show details on NVD website

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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Detection rules are retrieved from Rulezet.

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Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.


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