TI-2025-09274 Aliases CVE-2025-10101 GHSA-5wgw-665q-2r54

Avast antivirus heap buffer OOB read when scanning a malformed Mach-O file

LOW 35CWE-125Published 2025-12-01 · Updated 2026-06-12

Key facts

Attack vector: Local
Privileges required: None
User interaction: Required
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: High · High · High
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

Heap buffer out-of-bounds read vulnerability in Avast Antivirus when scanning a malformed Mach-O file may allow Local Execution of Code or Denial-of-Service of the antivirus process. This issue affects Avast Antivirus, AVG Antivirus, Norton Antivirus, Avast One, and Avast Business Antivirus on Windows, macOS, and Linux for virus definition builds before VPS 25090300. The affected scanning logic is delivered through a shared Gen Digital virus definition update stream. The same stream feeds the consumer antivirus products listed in this advisory and other Gen Digital products that embed the same engine. Mitigation flows through this update channel; installations at or above the listed build are not vulnerable regardless of which product consumes the stream.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00191 8th percentileScored 2026-11-07

Fix Fixed Avast Antivirus (Gen Digital): 25090300AVG Antivirus (Gen Digital): 25090300+3 more products

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Gen Digital	Avast Antivirus	before 25090300	25090300	Patch available	CNA
Gen Digital	AVG Antivirus	before 25090300	25090300	Patch available	CNA
Gen Digital	Norton Antivirus	before 25090300	25090300	Patch available	CNA
Gen Digital	Avast One	before 25090300	25090300	Patch available	CNA
Gen Digital	Avast Business Antivirus	before 25090300	25090300	Patch available	CNA

Avast Antivirus VendorGen Digital Affected before 25090300 Fixed in 25090300 Patch available CNA
AVG Antivirus VendorGen Digital Affected before 25090300 Fixed in 25090300 Patch available CNA
Norton Antivirus VendorGen Digital Affected before 25090300 Fixed in 25090300 Patch available CNA
Avast One VendorGen Digital Affected before 25090300 Fixed in 25090300 Patch available CNA
Avast Business Antivirus VendorGen Digital Affected before 25090300 Fixed in 25090300 Patch available CNA

Remediation

Fix · CNA Avast Antivirus (Gen Digital) Fixed in 25090300
Fix · CNA AVG Antivirus (Gen Digital) Fixed in 25090300
Fix · CNA Norton Antivirus (Gen Digital) Fixed in 25090300
Fix · CNA Avast One (Gen Digital) Fixed in 25090300
Fix · CNA Avast Business Antivirus (Gen Digital) Fixed in 25090300

Timeline

2026-10-02 Threatist record created from CVE-2025-10101
2026-10-03 Alias added: GHSA-5wgw-665q-2r54

References

Other 1

https://www.gendigital.com/us/en/contact-us/security-advisories/

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TI-2026-22110 Avira Internet Security Optimizer TOCTOU CVSS 3.1HIGH 7.8
TI-2026-22109 Avira Internet Security System Speedup Insecure Deserialization CVSS 3.1HIGH 7.8
TI-2026-22108 Avira Internet Security Arbitrary File Deletion via Improper Link Resolution CVSS 3.1HIGH 7.8
TI-2015-06072 Use-after-free vulnerability in the Update Manager service in Avira Management Console… CVSS 2.0HIGH 10.0
TI-2023-18488 An issue was discovered in Avira Phantom VPN through 2.23.1 for macOS. CVSS 3.1HIGH 7.3

See all 69 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences