VulnerabilityPublished 11 Nov 2025Updated 12 Nov 2025

CVE-2025-10905: Avast Free Antivirus · Protection Mechanism Failure

Affects Avast Free AntivirusSource CVE Database V5

Not known to be exploited · CVSS 4.4 Medium.

Data as of 26 Oct 2026, 14:05 UTC

CVSS 3.1 base score

4.4Medium

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

EPSS: 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Local
Attack Complexity: Low
Privileges Required: High
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: 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: High: The attacker is authorized with (i.e., requires) privileges that provide significant (e.g., administrative) control over the vulnerable component that could affect component-wide settings and files.
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 11 Nov 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 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

Affected software

Product	Affected	Fixed in
Avast Free Antivirus	Affected =0	Fixed in–

AI-suggested

To mitigate CVE-2025-10905, European organizations should implement the following specific measures: 1) Restrict administrative privileges strictly to trusted personnel and use the principle of least privilege to minimize the number of users with high-level access. 2) Employ robust endpoint detection and response (EDR) solutions that can detect suspicious activities even if antivirus protections are disabled. 3) Monitor system and driver behavior for anomalies indicative of MiniFilter driver tampering or disabling of antivirus components. 4) Enforce application whitelisting and code integrity policies to prevent unauthorized driver modifications. 5) Regularly audit and review administrative access logs to detect potential misuse. 6) Stay vigilant for Avast security advisories and promptly apply patches or updates once they become available to address this vulnerability. 7) Consider deploying layered security controls such as network segmentation and multi-factor authentication to reduce the impact of compromised administrative accounts. 8) Educate administrators on the risks associated with privilege misuse and the importance of maintaining endpoint security hygiene.

Description

Collision in MiniFilter driver in Avast Software Avast Free Antivirus before 25.9 on Windows allows a local attacker with administrative privileges to disable real-time protection and self-defense mechanisms.

Impact

For European organizations, the primary impact of CVE-2025-10905 lies in the potential degradation of endpoint security posture. By allowing an attacker with administrative privileges to disable real-time protection and self-defense, the vulnerability can facilitate the execution and persistence of malware, ransomware, or other malicious activities without detection. This can lead to increased risk of data loss, operational disruption, and potential lateral movement within networks. Although exploitation requires administrative access, insider threats or attackers who have already escalated privileges could leverage this vulnerability to undermine security controls. The absence of confidentiality and integrity impact reduces the risk of direct data breaches from this flaw alone, but the availability impact can indirectly lead to severe consequences. European organizations with large deployments of Avast Free Antivirus on Windows endpoints, especially in sectors like finance, healthcare, and critical infrastructure, could face increased exposure. The vulnerability also complicates incident response efforts by disabling self-defense mechanisms that protect the antivirus from tampering during an attack.

CWE-693Protection Mechanism Failure (opens in a new tab)
Pillar weaknessOWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
The product does not use or incorrectly uses a protection mechanism that provides sufficient defense against directed attacks against the product.
MITRE discourages mapping vulnerabilities to this broad entry; the root cause is usually a more specific weakness.
OWASP Cheat Sheets
Secure Design Principles (opens in a new tab)
Attack patterns
Accessing Functionality Not Properly Constrained by ACLs (opens in a new tab)
Cross Site Tracing (opens in a new tab)
Directory Indexing (opens in a new tab)
Using Malicious Files (opens in a new tab)
Encryption Brute Forcing (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

gendigital.com/us/en/contact-us/security-advisories/) (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 18 Nov 2025, 19:01 UTC

WeaknessesCWE-693

Technical details

References

Community reviews

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