CVE-2022-4291: Aswjsflt.dll in Avast Antivirus windows caused a crash of the Mozilla Firefox browser due to heap corruption

Severity: critical (CVSS 10.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-12-08 · updated 2026-06-17
Weakness: CWE-119

Description

The aswjsflt.dll library from Avast Antivirus windows contained a potentially exploitable heap corruption vulnerability that could enable an attacker to bypass the sandbox of the application it was loaded into, if applicable. This issue was fixed in version 18.0.1478 of the Script Shield Component.

Affected products

Avast Script Shield: through 18.0.1473.0

References

https://support.norton.com/sp/static/external/tools/security-advisories.html
https://support.norton.com/sp/static/external/tools/security-advisories.html

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