CVE-2021-23982

MEDIUM
6.5
CVSS Score
Published: March 31, 2021 at 01:42 PM UTC
Updated: June 17, 2026 at 03:39 AM UTC
3 products affected across 1 vendorFirefoxThunderbirdFirefox ESR

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Severity
MEDIUM6.5
Exploit prediction
EPSS 0.7%

Description

Using techniques that built on the slipstream research, a malicious webpage could have scanned both an internal network's hosts as well as services running on the user's local machine utilizing WebRTC connections. This vulnerability affects Firefox ESR < 78.9, Firefox < 87, and Thunderbird < 78.9.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 87
Affected range stops below 87, so it looks safe — our inference, not a vendor statement
Affected range stops below 87.0, so it looks safe — our inference, not a vendor statement
v < 78.9
Affected range stops below 78.9, so it looks safe — our inference, not a vendor statement
v < 78.9
Affected range stops below 78.9, so it looks safe — our inference, not a vendor statement

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-326

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