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Linux Kernel EUVDEUVD-2026-45498

| CVE-2026-63832 HIGH
Improper Synchronization (CWE-662)
2026-07-19 Linux GHSA-xq4q-93xc-52g2
8.8
CVSS 3.1 · Vendor: Linux
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Attack ChainAIDerived

Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain

  1. Access
    Attacker within WiFi range
  2. Delivery
    Force client re-association/roaming
  3. Exploit
    Trigger duplicate wcid poll_list init
  4. Execution
    Corrupt dev->sta_poll_list
  5. Persist
    RX/TX-status poll dereferences broken list
  6. Impact
    Kernel panic (denial of service)

Vulnerability Assessment

Weakness
CWE
Exploitation Conditions

Exploitation requires the target to be running an affected Linux kernel with the mt76/mt7925 driver active and MediaTek MT7925 wireless hardware in use - the bug is reached specifically through the station-add path during WiFi (re)association/roaming, as shown by the disconnect/authenticate sequence in the report and the mt76_wcid_add_poll → mt7925_mac_add_txs call chain. Limiting factors: the system must actually use the MT7925 chipset and the vulnerable driver, exposure is adjacent-network (AV:A, WiFi radio range) rather than routable Internet, and triggering depends on association/roaming timing that resembles a race window, so it is not deterministically attacker-controlled against a default idle configuration. Systems without MT7925 hardware or with the mt7925 driver unloaded are not affected.

Impact

The supplied CVSS 3.1 score is 8.8 with vector AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, implying adjacent-network, low-complexity, unauthenticated full-impact compromise. Several signals argue this overstates real-world risk: EPSS is only 0.15% (5th percentile), there is no KEV listing and no public exploit, and the described root cause is a linked-list corruption triggered by internal driver state during association rather than a cleanly attacker-controlled primitive. The C:H/I:H rating conflicts with the actual evidence, which shows a kernel panic (availability/DoS) as the realistic outcome; turning list corruption into reliable code execution on modern kernels with hardened list checks is difficult and unproven here. The tag 'Information Disclosure' also conflicts with the described list-corruption crash and should be treated with skepticism. AC:L is questionable because the corruption appears tied to specific association/roaming timing (a race-like window), so AC:H is more defensible. Net: this is a legitimate memory-corruption bug worth patching, but current evidence supports a local/adjacent denial-of-service priority rather than a confirmed remote code execution emergency.

Exploit ScenarioDerived

A user with an MT7925 adapter roams between or reconnects to WiFi access points (as in the reported log where the client re-authenticates to a nearby AP); during the resulting station-add path the driver corrupts its sta_poll_list, and subsequent RX/TX-status processing dereferences the broken list and panics the kernel. An attacker within WiFi range could plausibly provoke repeated re-association (for example by spoofing or disrupting APs to force roaming) to trigger the crash as a denial of service. No public proof-of-concept is known, and reliable code execution from this corruption is unproven.

This Week Schedule remediation this week. Why: HIGH severity (CVSS 7.0-8.9).
Patch available 0.2% exploitation probability (EPSS)

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AnalysisAIv1 – Jul 20, 2026

Memory corruption in the Linux kernel mt76 WiFi driver (mt7925 chipset support) occurs because mt76_sta_add reinitializes the wcid->poll_list even though mt7925_mac_sta_add has already published the wcid, corrupting the dev->sta_poll_list linked list during station association. The flaw manifests as list_add corruption (observed on kernel 7.1-rc4 with mt7925 hardware) reachable from the RX NAPI poll path when TX status frames are processed, typically leading to a kernel panic. This is a vendor-fixed Linux stable-tree issue with no public exploit identified at time of analysis and a low EPSS score (0.15%).

RemediationAI

Vendor-released patch: update to Linux kernel 6.18.38 or 7.1.3 (or mainline 7.2-rc1 or later), which add the wcid publish check in mt76_sta_add so the poll_list is not reinitialized; the corresponding stable commits are 3c499851753a24d2e148d4e9ca51764c0c51554e, 55e014aaec650ede08b693ba59c8d0443f13f11c, and 20b126920a259df4d7dcae19fcfe2c57a74d6b2e at git.kernel.org. Apply the distribution kernel update that incorporates these commits and reboot. Where immediate patching is not possible, the practical compensating control is to avoid using the affected MT7925 WiFi interface - unload or blacklist the mt7925 driver modules (mt7925_common/mt792x_lib/mt76) and use a wired connection or an alternative WiFi adapter, accepting the trade-off of losing wireless connectivity; reducing roaming between access points may lower the chance of triggering the association-time corruption but is not a reliable fix. Consult the NVD advisory at https://nvd.nist.gov/vuln/detail/CVE-2026-63832 and your distribution's security tracker for backport availability.

Affected VersionsENISA

Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3c499851753a24d2e148d4e9ca51764c0c51554e
Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <20b126920a259df4d7dcae19fcfe2c57a74d6b2e
Linux 0 <6.18.38
Linux patch: 7.2-rc1
Linux patch: 7.1.3
Linux 0 <7.1.3
Linux patch: 6.18.38
Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <55e014aaec650ede08b693ba59c8d0443f13f11c

Affected Packages

euvd linux fix: 6.18.38, 7.1.3

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 1 package in euvd

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

The affected component is the mt76 mac80211 driver framework in the Linux kernel and its mt7925 sub-driver (used for MediaTek MT7925 WiFi 6E/7 client adapters common in recent laptops). Each associated station is represented by a wcid (wireless client ID) structure that is linked into a per-device sta_poll_list to schedule statistics polling. The bug is a double-initialization / list-management error: mt7925_mac_sta_add already publishes the wcid and its poll_list node, but the generic mt76_sta_add path re-initializes wcid->poll_list, breaking the doubly-linked list invariant (the reported corruption shows prev->next pointing back to itself). Although no CWE was assigned in the input, this maps to the CWE-416 (use-after-free) / CWE-665 (improper initialization) / CWE-824 (access of uninitialized pointer) class of linked-list corruption bugs, with the concrete symptom being list_add corruption detected by the kernel's list debugging.

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  • Exploit and PoC references, threat intelligence from 22 sources

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Severity by source

Vendor (Linux) PRIMARY 8.8 HIGH
AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vuln.today AI 5.3 MEDIUM

Adjacent WiFi radio access (AV:A); triggering depends on association/roaming timing (AC:H); no auth or interaction; evidence shows kernel panic so A:H with no confirmed confidentiality/integrity impact.

3.1 AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
4.0 AV:A/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SUSE 5.5 MEDIUM
AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Red Hat 5.5 MEDIUM

Primary rating from Vendor (Linux).

CVSS VectorVendor: Linux

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

Lifecycle Timeline

4
CVSS changed
Jul 20, 2026 - 15:22 NVD
8.8 (HIGH)
Patch available
Jul 19, 2026 - 14:17 EUVD
CVE Published
Jul 19, 2026 - 12:02 cve.org
HIGH 8.8
CVE Published
Jul 19, 2026 - 12:02 cve.org
UNKNOWN (no severity yet)

DescriptionCVE.org

In the Linux kernel, the following vulnerability has been resolved:

wifi: mt76: add wcid publish check in mt76_sta_add

Since mt7925_mac_sta_add publishes wcid, add publish check in mt76_sta_add to avoid reinitializing the wcid->poll_list.

Found dev->sta_poll_list corruption when using mt7925 and 7.1-rc4. According to the corruption information, prev->next was changed to itself.

wlan0: disconnect from AP 90:fb:5d:94:8b:e3 for new auth to 90:fb:5d:94:8b:e2 wlan0: authenticate with 90:fb:5d:94:8b:e2 (local address=84:9e:56:9c:7e:6b) wlan0: send auth to 90:fb:5d:94:8b:e2 (try 1/3) slab kmalloc-8k start ffff8c80958a6000 pointer offset 4160 size 8192 list_add corruption. prev->next should be next (ffff8c808a7488f8), but was ffff8c80958a7040. (prev=ffff8c80958a7040).

mt76_wcid_add_poll+0x95/0xd0 [mt76] mt7925_mac_add_txs.part.0+0xa5/0xe0 [mt7925_common] mt7925_rx_check+0xa7/0xc0 [mt7925_common] mt76_dma_rx_poll+0x50d/0x790 [mt76] mt792x_poll_rx+0x52/0xe0 [mt792x_lib]

Executive ViewAI

Why It Matters

The Linux kernel mt76 WiFi driver (mt7925 chipset) contains a memory corruption vulnerability (CVSS 8.8) that causes kernel panics during station association, directly threatening system availability. Organizations with mt7925 WiFi hardware on Linux systems face unexpected system crashes that could disrupt critical operations.

Business Impact: High
Compensating Controls

Apply vendor patch.

Threat Intelligence Overview

EPSS Score
0.2%
Top 95% exploitable
Prevalence
High
Linux kernel is ubiquitous, but only MT7925 WiFi hardware users are affected
Data Quality
6 sources
Confidence: High

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity HIGH
CISA KEV No
Public POC No
EPSS 0.2%
Patch available Yes
Active threat No
Deciding rule
HIGH severity (CVSS 7.0-8.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation· derived
None
System Exposure· derived
Controlled
Automatable· derived
No
Human Impact
High

Priority Score

44
Low Medium High Critical
KEV: 0
EPSS: 0
CVSS: +44
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.

Vendor StatusVendor

SUSE

Severity: Moderate
Product Status
SUSE Linux Enterprise Desktop 15 SP7 Not-Affected
SUSE Linux Enterprise Desktop 15 SP7 Not-Affected
SUSE Linux Enterprise High Availability Extension 15 SP7 Not-Affected
SUSE Linux Enterprise High Availability Extension 15 SP7 Not-Affected
SUSE Linux Enterprise High Availability Extension 16.0 Affected

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