VulnerabilityPublished 3 Jun 2026Updated 19 Oct 2026

CVE-2026-46244: Linux kernel · netfilter: nft_inner: Fix IPv6 inner_thoff desync

Affects Linux kernelSource CVE Database V5

Not known to be exploited · CVSS 9.1 Critical · fixed in d0f98a3617f6ae5b1e95cde1e68e7ead4a1279ce : patch Linux kernel as a priority.

Data as of 26 Oct 2026, 12:42 UTC

CVSS 3.1 base score

9.1Critical

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

EPSS

0.4% chance of exploitation in 30 days – higher than 35% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

Exploitation: No evidence of active exploitation and no public proof of concept
Automatable: Attackers can reliably automate steps 1–4 of the kill chain
Technical impact: Total control over the software or total information disclosure

CISA SSVC assessment, 2026-10-16.

Patch

Available – fixed in d0f98a3617f6ae5b1e95cde1e68e7ead4a1279ce, c161ad9157f5a0429b5ff94d9770faf3bf48d273, b6a91f68ebfed9c38e0e9150f58a9b85da07181c +2

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

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

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: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 3 Jun 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 ≥ 3a07327d10a09379315c844c63f27941f5081e0a, < d0f98a3617f6ae5b1e95cde1e68e7ead4a1279ce	Fixed in d0f98a3617f6ae5b1e95cde1e68e7ead4a1279ce
LinuxLinux	Affected ≥ 3a07327d10a09379315c844c63f27941f5081e0a, < c161ad9157f5a0429b5ff94d9770faf3bf48d273	Fixed in c161ad9157f5a0429b5ff94d9770faf3bf48d273
LinuxLinux	Affected ≥ 3a07327d10a09379315c844c63f27941f5081e0a, < b6a91f68ebfed9c38e0e9150f58a9b85da07181c	Fixed in b6a91f68ebfed9c38e0e9150f58a9b85da07181c
LinuxLinux	Affected ≥ 3a07327d10a09379315c844c63f27941f5081e0a, < 870d59e2cf218e7418491e26bad768cb16654582	Fixed in 870d59e2cf218e7418491e26bad768cb16654582
LinuxLinux	Affected ≥ 3a07327d10a09379315c844c63f27941f5081e0a, < 689bbf48c1f45130086ae1c46ab83ea4c753c601	Fixed in 689bbf48c1f45130086ae1c46ab83ea4c753c601
LinuxLinux	Affected =6.2	Fixed in–

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_inner: Fix IPv6 inner_thoff desync In nft_inner_parse_l2l3(), when processing inner IPv6 packets, ipv6_find_hdr() correctly computes the transport header offset traversing all extension headers, but the result is immediately overwritten with nhoff + sizeof(_ip6h) (40 bytes), which only accounts for the IPv6 base header. This creates a desync between inner_thoff (wrong — points to extension header start) and l4proto (correct — e.g., IPPROTO_TCP), enabling transport header forgery and potential firewall bypass. This issue affects stable versions from Linux 6.2. For comparison, the normal (non-inner) IPv6 path correctly preserves ipv6_find_hdr()'s result. Removing the incorrect overwrite ensures that ipv6_find_hdr()'s calculated transport header offset is preserved, thereby fixing the desynchronization.

CWE-823Use of Out-of-range Pointer Offset (opens in a new tab)
Base weakness
The product performs pointer arithmetic on a valid pointer, but it uses an offset that can point outside of the intended range of valid memory locations for the resulting pointer.
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
Pointer Manipulation (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-682Incorrect Calculation (opens in a new tab)
Pillar weaknessLikelihood of exploit: High
The product performs a calculation that generates incorrect or unintended results that are later used in security-critical decisions or resource management.
MITRE discourages mapping vulnerabilities to this broad entry; the root cause is usually a more specific weakness.
Implementation
Understand your programming language's underlying representation and how it interacts with numeric calculation. Pay close attention to byte size discrepancies, precision, signed/unsigned distinctions, truncation, conversion and casting between types, "not-a-number" calculations, and how your language handles numbers…
Implementation · Input Validation
Perform input validation on any numeric input by ensuring that it is within the expected range. Enforce that the input meets both the minimum and maximum requirements for the expected range.
Implementation
Use the appropriate type for the desired action. For example, in C/C++, only use unsigned types for values that could never be negative, such as height, width, or other numbers related to quantity.
Attack patterns
Integer Attacks (opens in a new tab)
Pointer Manipulation (opens in a new tab)
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

WeaknessesCWE-823, CWE-682

Technical details

References

Community reviews

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