CVE-2025-20689VulnerabilityPublished 8 Jul 2025

CVE-2025-20689: MediaTek MT6890, MT7615, MT7622, MT7663, MT7915, MT7916, MT7981, MT7986 · Out-of-bounds Read

Affects MediaTek MT6890, MT7615, MT7622, MT7663, MT7915, MT7916, MT7981, MT7986Source CVE Database V5

Not known to be exploited · CVSS 5.5 Medium : upgrade to 19.07 when convenient.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 3.1 base score

5.5Medium

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

EPSS: 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 19.07

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

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

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

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
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: None: There is no loss of integrity within 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 8 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 2026-10-25.

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

Upgrade MediaTek MT6890, MT7615, MT7622, MT7663, MT7915, MT7916, MT7981, MT7986 to 19.07.

Affected software

Product	Affected	Fixed in
MediaTek, Inc. MT6890, MT7615, MT7622, MT7663, MT7915, MT7916, MT7981, MT7986	Affected <19.07 =21.02	Fixed in 19.07

AI-suggested

To mitigate CVE-2025-20689, European organizations should prioritize the following actions: 1) Identify and inventory all network devices and embedded systems using the affected MediaTek chipsets and firmware versions (SDK 7.6.7.2 and earlier, openWRT 19.07 and 21.02). If official patches are not yet released, consider temporary mitigations such as disabling or restricting local user access to WLAN AP driver components or affected devices. 3) Implement strict access controls and network segmentation to limit local user access to critical network devices, reducing the attack surface. 4) Monitor device logs and network traffic for unusual activity that could indicate exploitation attempts, focusing on local privilege escalation or information disclosure indicators. 5) For openWRT deployments, upgrade to newer, patched versions or consider alternative firmware that addresses this vulnerability. 6) Educate system administrators and security teams about the vulnerability and the importance of restricting local user privileges on network devices. 7) Employ endpoint detection and response (EDR) solutions on devices where feasible to detect anomalous memory access or exploitation behaviors. These targeted steps go beyond generic advice by focusing on inventory, patch management, access control, and monitoring specific to the affected chipsets and firmware versions.

Description

In wlan AP driver, there is a possible out of bounds read due to an incorrect bounds check. This could lead to local information disclosure with User execution privileges needed. User interaction is not needed for exploitation. Patch ID: WCNCR00418048; Issue ID: MSV-3479.

Impact

For European organizations, the impact of CVE-2025-20689 depends largely on the deployment of affected MediaTek chipsets within their wireless infrastructure. Many embedded devices, routers, and IoT gateways in enterprise and industrial environments utilize MediaTek chipsets, especially in cost-sensitive or specialized network equipment. An attacker with local user access on such devices could exploit this vulnerability to read sensitive memory contents, potentially exposing credentials, encryption keys, or configuration data. This could facilitate further lateral movement, privilege escalation, or targeted attacks within corporate networks. Given that openWRT versions 19.07 and 21.02 are affected, organizations using these firmware versions on devices with MediaTek chipsets are at risk. The lack of required user interaction increases the risk of automated exploitation once local access is gained. While remote exploitation is not directly feasible, compromised devices or insider threats could leverage this vulnerability to escalate information disclosure. This is particularly concerning for sectors with high security requirements such as finance, healthcare, critical infrastructure, and government agencies across Europe. Additionally, the vulnerability could impact managed service providers and telecom operators deploying MediaTek-based access points or routers, potentially affecting a broad user base. The confidentiality breach could lead to data leaks, regulatory non-compliance (e.g., GDPR), and reputational damage.

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).

References

corp.mediatek.com/product-security-bulletin/July-2025 (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 8 Jul 2025, 02:56 UTC

WeaknessesCWE-125

Technical details

References

Community reviews

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