CVE-2024-21386VulnerabilityPublished 14 Feb 2024Updated 13 Aug 2026

Red Hat Security Advisory: .NET 6.0 security, bug fix, and enhancement update

Affects Red HatSource GCVE Database

Mentioned vulnerabilities

CVE-2024-21404

Not known to be exploited.

Data as of 26 Oct 2026, 07:57 UTC

Severity

High

Rated by Threat Radar · No CVSS score from NVD or the CNA

EPSS: 2.4% chance of exploitation in 30 days – higher than 84% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

Exploitation evidence

Disclosed: evidence found.
CVE published 14 Feb 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

AI-suggested

Red Hat has released updated .NET 6.0 packages (SDK 6.0.127 and Runtime 6.0.27) that address these denial of service vulnerabilities. Users should apply these updates promptly to remediate the issues. Detailed update instructions are available in the Red Hat advisory (RHSA-2024:0814) and related knowledge base articles. No additional mitigation steps are indicated or required beyond applying the official patches.

Description

.NET 6.0 on Red Hat Enterprise Linux has received an important security update addressing two denial of service vulnerabilities. The affected components include the SignalR server and the X509Certificate2 class. Updated versions .NET SDK 6.0.127 and .NET Runtime 6.0.27 contain fixes for these issues. The vulnerabilities are tracked as CVE-2024-21386 and CVE-2024-21404. Red Hat has released patched packages for RHEL 7 to remediate these flaws.

Impact

Successful exploitation of these vulnerabilities could result in denial of service conditions affecting applications using the SignalR server or the X509Certificate2 class in .NET 6.0 on Red Hat Enterprise Linux. This could disrupt service availability but does not indicate code execution or data compromise. The impact is rated as Important by Red Hat, indicating a high severity level for service disruption.

CWE-400Uncontrolled Resource Consumption (opens in a new tab)
Class weaknessLikelihood of exploit: High
The product does not properly control the allocation and maintenance of a limited resource.
MITRE discourages mapping vulnerabilities to this broad entry; the root cause is usually a more specific weakness.
Architecture and Design
Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended. A strong authentication and access control model will help prevent such attacks from occurring in the first place.
Architecture and Design
Mitigation of resource exhaustion attacks requires that the target system either: recognizes the attack and denies that user further access for a given amount of time, or; uniformly throttles all requests in order to make it more difficult to consume resources more quickly than they can again be freed.
Architecture and Design
Ensure that protocols have specific limits of scale placed on them.
OWASP Cheat Sheets
File Upload (opens in a new tab)
OWASP ASVS 4.0.3
V12.1.1 (opens in a new tab)
Attack patterns
XML Ping of the Death (opens in a new tab)
Regular Expression Exponential Blowup (opens in a new tab)
Sustained Client Engagement (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 13 Aug 2026, 17:49 UTC

WeaknessesCWE-400

Technical details

References

Community reviews

Related threats