CVE-2026-45859VulnerabilityPublished 15 Oct 2026Updated 26 Oct 2026

Red Hat Security Advisory: kernel security, bug fix, and enhancement update

Affects Red Hat kernel security,Source GCVE Database

Mentioned vulnerabilities

Authoritative record:CVE-2026-45859· High 7.5

Not known to be exploited · CVSS 7.5 High · fixed in Red Hat package updates : patch Red Hat kernel security, soon.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.6% chance of exploitation in 30 days – higher than 51% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in b740e7ddd7ca0dbfeafca3f5e52717206cf28524, aead84bdacd77e08357fd718e5dcaffaf387f3c3, 23901aa6b8a2f294c4b774436b4691f3ff863a8f +6

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 27 May 2026
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 or the CVSS exploit maturity 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

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected >=6.6.48 <6.6.160 >=5.15.166 <5.16 >=6.1.107 <6.2 >=6.10.7 <6.11	Fixed in b740e7ddd7ca0dbfeafca3f5e52717206cf28524 aead84bdacd77e08357fd718e5dcaffaf387f3c3 23901aa6b8a2f294c4b774436b4691f3ff863a8f 207b3ebacb6113acaaec0d171d5307032c690004 79b713ef4261a8ead96af4703f89d0b5f25532e2 6.11 6.6.160 6.2 5.16
LinuxLinux	Affected =6.11	Fixed in–

Description

The kernel packages contain the Linux kernel, the core of any Linux operating system. Security Fix(es): * kernel: netfilter: nfnetlink_queue: do shared-unconfirmed check before segmentation (CVE-2026-45859) * kernel: net/sched: act_ct: Only release RCU read lock after ct_ft (CVE-2026-46319) * kernel: net/sched: taprio: fix use-after-free in advance_sched() on schedule switch (CVE-2026-53011) * kernel: USB: serial: mxuport: fix memory corruption with small endpoint (CVE-2026-63899) * kernel: bridge: mcast: Fix a possible use-after-free when removing a bridge port (CVE-2026-64032) * kernel: wifi: mac80211: bounds-check link_id in ieee80211_ml_epcs (CVE-2026-64030) * kernel: Bluetooth: hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close (CVE-2026-63974) * kernel: idpf: fix read_dev_clk_lock spinlock init in idpf_ptp_init() (CVE-2026-64162) * kernel: Linux kernel: Denial of Service due to use-after-free in act_tunnel_key (CVE-2026-68377) * kernel: net/iucv: fix use-after-free of a severed iucv_path (CVE-2026-68140) * kernel: ASoC: SOF: ipc3-control: Fix heap overflow in bytes_ext put/get (CVE-2026-72262) * kernel: dmaengine: idxd: fix fdev setup failure cleanup in idxd_cdev_open() (CVE-2026-74574) * kernel: ALSA: usx2y: bound the hwdep mmap fault offset (CVE-2026-74641) * kernel: net/smc: carry oversized SMC-Rv2 LLC messages in the queue entry (CVE-2026-80985) * kernel: svcrdma: Validate Read chunk positions before reconstruction (CVE-2026-89526) * kernel: nfsd: don't free session slots that are still in use (CVE-2026-89689) * kernel: NFSD: Prevent client use-after-free during blocked-lock reaping (CVE-2026-90036) * kernel: media: cx231xx: reject geometry changes while the VBI queue is busy (CVE-2026-89894) * kernel: SUNRPC: Zero rpc_gss_wire_cred at svcauth_gss_decode_credbody() entry (CVE-2026-93207) * kernel: svcrdma: Reject Write/Reply chunks with segcount 0 (CVE-2026-93228) Bug Fix(es) and Enhancement(s): * cannot use VFs of i40e/ice NIC in bond device (JIRA:RHEL-143410) * ionic: commit backported to 9.8 missing in 10.2 (JIRA:RHEL-165657) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

CWE-367Time-of-check Time-of-use (TOCTOU) Race Condition (opens in a new tab)
Base weaknessLikelihood of exploit: Medium
The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.
Implementation
The most basic advice for TOCTOU vulnerabilities is to not perform a check before the use. This does not resolve the underlying issue of the execution of a function on a resource whose state and identity cannot be assured, but it does help to limit the false sense of security given by the check.
Implementation
When the file being altered is owned by the current user and group, set the effective gid and uid to that of the current user and group when executing this statement.
Architecture and Design
Limit the interleaving of operations on files from multiple processes.
OWASP Cheat Sheets
Abuse Case (opens in a new tab)
OWASP ASVS 4.0.3
V1.11.3 (opens in a new tab)
V11.1.6 (opens in a new tab)
V1.11.2 (opens in a new tab)
Attack patterns
Leveraging Race Conditions via Symbolic Links (opens in a new tab)
Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-826Premature Release of Resource During Expected Lifetime (opens in a new tab)
Base weakness
The product releases a resource that is still intended to be used by itself or another actor.
CWE-825Expired Pointer Dereference (opens in a new tab)
Base weakness
The product dereferences a pointer that contains a location for memory that was previously valid, but is no longer valid.
Architecture and Design
Choose a language that provides automatic memory management.
Implementation
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-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #11
The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.
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
Docker Security (opens in a new tab)
XML Security (opens in a new tab)
OWASP ASVS 4.0.3
V5.4.1 (opens in a new tab)
V14.1.2 (opens in a new tab)
V13.3.1 (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-366Race Condition within a Thread (opens in a new tab)
Base weaknessLikelihood of exploit: Medium
If two threads of execution use a resource simultaneously, there exists the possibility that resources may be used while invalid, in turn making the state of execution undefined.
Architecture and Design
Use locking functionality. This is the recommended solution. Implement some form of locking mechanism around code which alters or reads persistent data in a multithreaded environment.
Architecture and Design
Create resource-locking validation checks. If no inherent locking mechanisms exist, use flags and signals to enforce your own blocking scheme when resources are being used by other threads of execution.
OWASP Cheat Sheets
Abuse Case (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-476NULL Pointer Dereference (opens in a new tab)
Base weaknessLikelihood of exploit: MediumCWE Top 25 (2025): #13OWASP Top 10 A10:2025: Mishandling of Exceptional Conditions (opens in a new tab)
The product dereferences a pointer that it expects to be valid but is NULL.
Implementation
For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished.
Requirements
Select a programming language that is not susceptible to these issues.
Implementation
Check the results of all functions that return a value and verify that the value is non-null before acting upon it.
OWASP Cheat Sheets
Logging (opens in a new tab)
Error Handling (opens in a new tab)
OWASP ASVS 4.0.3
V11.1.7 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-909Missing Initialization of Resource (opens in a new tab)
Class weaknessLikelihood of exploit: Medium
The product does not initialize a critical resource.
Implementation
Explicitly initialize the resource before use. If this is performed through an API function or standard procedure, follow all specified 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-787Out-of-bounds Write (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #5
The product writes data past the end, or before the beginning, of the intended buffer.
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)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-833Deadlock (opens in a new tab)
Base weakness
The product contains multiple threads or executable segments that are waiting for each other to release a necessary lock, resulting in deadlock.
Attack patterns
Forced Deadlock (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-125Out-of-bounds Read (opens in a new tab)
Base weaknessCWE Top 25 (2025): #8
The product reads data past the end, or before the beginning, of the intended buffer.
Implementation · Input Validation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
Architecture and Design · Language Selection
Use a language that provides appropriate memory abstractions.
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
Overread Buffers (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-839Numeric Range Comparison Without Minimum Check (opens in a new tab)
Base weakness
The product checks a value to ensure that it is less than or equal to a maximum, but it does not also verify that the value is greater than or equal to the minimum.
Implementation · Enforcement by Conversion
If the number to be used is always expected to be positive, change the variable type from signed to unsigned or size_t.
Implementation · Input Validation
If the number to be used could have a negative value based on the specification (thus requiring a signed value), but the number should only be positive to preserve code correctness, then include a check to ensure that the value is positive.
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

GCVE source: db.gcve.eu
Csaf Category: csaf_security_advisory
Csaf Version: 2.0
Publisher: Red Hat Product Security
Advisory ID: RHSA-2026:83207
Vendor Severity: high
CVE Count: 20
Additional Cves: CVE-2026-46319, CVE-2026-53011, CVE-2026-63899, CVE-2026-63974, CVE-2026-64030, CVE-2026-64032, CVE-2026-64162, CVE-2026-68140, CVE-2026-68377, CVE-2026-72262, CVE-2026-74574, CVE-2026-74641, CVE-2026-80985, CVE-2026-89526, CVE-2026-89689, CVE-2026-89894, CVE-2026-90036, CVE-2026-93207, CVE-2026-93228

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

WeaknessesCWE-367, CWE-826, CWE-825 +8

Technical details

References

Community reviews

Related threats