CVE-2024-28956VulnerabilityPublished 14 Jul 2025Updated 13 Oct 2026

Red Hat Security Advisory: microcode_ctl security update

Affects Red HatSource GCVE Database

Not known to be exploited.

Data as of 26 Oct 2026, 08:30 UTC

Severity

High

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

EPSS: 0.4% chance of exploitation in 30 days – higher than 36% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

Exploitation evidence

Disclosed: evidence found.
CVE published 14 Jul 2025
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 26 Oct 2026.

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

Affected software

Product	Affected	Fixed in
Red Hatredhat/kernel`pkg:rpm/redhat/kernel`Other threats	Affected *	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Red Hat has released official security updates for the Linux kernel and microcode_ctl packages in Red Hat Enterprise Linux 9 to address CVE-2024-28956. Users should apply these updates promptly and reboot their systems to ensure the fixes take effect. Following the vendor's update and reboot instructions fully mitigates this vulnerability.

Description

CVE-2024-28956 is an information disclosure vulnerability affecting some Intel processors, involving exposure of sensitive information through shared microarchitectural structures during transient execution. It requires local authenticated access and has a medium severity rating with a CVSS score of 5.7. Red Hat has released security updates for the Linux kernel and microcode_ctl packages in Red Hat Enterprise Linux 9 to address this issue. Users must apply these updates and reboot their systems to mitigate the vulnerability.

CWE-1421Exposure of Sensitive Information in Shared Microarchitectural Structures during Transient Execution (opens in a new tab)
Base weakness
A processor event may allow transient operations to access architecturally restricted data (for example, in another address space) in a shared microarchitectural structure (for example, a CPU cache), potentially exposing the data over a covert channel.
Architecture and Design
Hardware designers may choose to engineer the processor's pipeline to prevent architecturally restricted data from being used by operations that can execute transiently.
Architecture and Design
Hardware designers may choose not to share microarchitectural resources that can contain sensitive data, such as fill buffers and store buffers.
Architecture and Design
Hardware designers may choose to sanitize specific microarchitectural state (for example, store buffers) when the processor transitions to a different context, such as whenever a system call is invoked.
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-416Use After Free (opens in a new tab)
Variant weaknessLikelihood of exploit: HighCWE Top 25 (2025): #7
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
Architecture and Design · Language Selection
Choose a language that provides automatic memory management.
Implementation · Attack Surface Reduction
When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-200Exposure of Sensitive Information to an Unauthorized Actor (opens in a new tab)
Class weaknessLikelihood of exploit: HighCWE Top 25 (2025): #20OWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
MITRE discourages mapping vulnerabilities to this broad entry; the root cause is usually a more specific weakness.
Architecture and Design · Separation of Privilege
Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
OWASP Cheat Sheets
Error Handling (opens in a new tab)
Logging (opens in a new tab)
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V8.3.4 (opens in a new tab)
V14.3.3 (opens in a new tab)
V7.3.3 (opens in a new tab)
Attack patterns
Subverting Environment Variable Values (opens in a new tab)
ICMP Echo Request Ping (opens in a new tab)
TCP SYN Scan (opens in a new tab)
Enumerate Mail Exchange (MX) Records (opens in a new tab)
DNS Zone Transfers (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-704Incorrect Type Conversion or Cast (opens in a new tab)
Class weakness
The product does not correctly convert an object, resource, or structure from one type to a different type.
CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer (opens in a new tab)
Class weaknessLikelihood of exploit: High
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
MITRE discourages mapping vulnerabilities to this broad entry; the root cause is usually a more specific weakness.
Requirements · Language Selection
Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Operation · Build and Compilation · Environment Hardening
Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index…
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
Attack patterns
Buffer Overflow via Environment Variables (opens in a new tab)
Overflow Buffers (opens in a new tab)
Client-side Injection-induced Buffer Overflow (opens in a new tab)
Filter Failure through Buffer Overflow (opens in a new tab)
MIME Conversion (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') (opens in a new tab)
Class weaknessLikelihood of exploit: MediumOWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.
Architecture and Design
In languages that support it, use synchronization primitives. Only wrap these around critical code to minimize the impact on performance.
Architecture and Design
Use thread-safe capabilities such as the data access abstraction in Spring.
Architecture and Design
Minimize the usage of shared resources in order to remove as much complexity as possible from the control flow and to reduce the likelihood of unexpected conditions occurring.
OWASP Cheat Sheets
Abuse Case (opens in a new tab)
Secure Design Principles (opens in a new tab)
OWASP ASVS 4.0.3
V1.11.2 (opens in a new tab)
Attack patterns
Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions (opens in a new tab)
Leveraging Race Conditions (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-908Use of Uninitialized Resource (opens in a new tab)
Base weaknessLikelihood of exploit: Medium
The product uses or accesses a resource that has not been initialized.
Implementation
Explicitly initialize the resource before use. If this is performed through an API function or standard procedure, follow all required steps.
Implementation
Pay close attention to complex conditionals that affect initialization, since some branches might not perform the initialization.
Implementation
Avoid race conditions (CWE-362) during initialization routines.
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-1423Exposure of Sensitive Information caused by Shared Microarchitectural Predictor State that Influences Transient Execution (opens in a new tab)
Base weakness
Shared microarchitectural predictor state may allow code to influence transient execution across a hardware boundary, potentially exposing data that is accessible beyond the boundary over a covert channel.
Architecture and Design
The hardware designer can attempt to prevent transient execution from causing observable discrepancies in specific covert channels.
Architecture and Design
Hardware designers may choose to use microarchitectural bits to tag predictor entries. For example, each predictor entry may be tagged with a kernel-mode bit which, when set, indicates that the predictor entry was created in kernel mode.
Architecture and Design
Hardware designers may choose to sanitize microarchitectural predictor state (for example, branch prediction history) when the processor transitions to a different context, for example, whenever a system call is invoked.
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-696Incorrect Behavior Order (opens in a new tab)
Class weakness
The product performs multiple related behaviors, but the behaviors are performed in the wrong order in ways that may produce resultant weaknesses.
Attack patterns
Padding Oracle Crypto Attack (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-1419Incorrect Initialization of Resource (opens in a new tab)
Class weakness
The product attempts to initialize a resource but does not correctly do so, which might leave the resource in an unexpected, incorrect, or insecure state when it is accessed.
Implementation
Choose the safest-possible initialization for security-related resources.
Implementation
Ensure that each resource (whether variable, memory buffer, register, etc.) is fully initialized.
Implementation
Pay close attention to complex conditionals or reset sources that affect initialization, since some paths might not perform the initialization.
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 11 Oct 2026, 22:24 UTC

WeaknessesCWE-1421, CWE-416, CWE-200 +7

Technical details

References

Community reviews

Related threats