CVE-2026-8970

Privilege escalation in the Security component

HIGH
8.8
CVSS Score
Published: May 19, 2026 at 12:30 PM UTC
Updated: July 23, 2026 at 09:11 PM UTC
2 products affected across 1 vendorFirefoxThunderbird

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Severity
HIGH8.8
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

Privilege escalation in the Security component. This vulnerability was fixed in Firefox 151 and Firefox ESR 140.11.

Affected

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

v < 140.11.0v < 151.0.0
Vendor states this is fixed in 140.11 (unaffected)
Affected range stops below 140.11.0, so it looks safe — our inference, not a vendor statement
Vendor states this is fixed in 151 (unaffected)
Affected range stops below 151.0.0, so it looks safe — our inference, not a vendor statement
v < 140.11v < 151.0.0
Vendor states this is fixed in 140.11 (unaffected)
Vendor states this is fixed in 151 (unaffected)
Affected range stops below 151.0.0, so it looks safe — our inference, not a vendor statement

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.8HIGHCISA-ADP
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-269

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