CVE-2021-23998
MEDIUM
6.5
CVSS Score
Published: June 24, 2021 at 01:25 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 0.6%
Description
Through complicated navigations with new windows, an HTTP page could have inherited a secure lock icon from an HTTPS page. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
v < 88
Affected range stops below 88, so it looks safe — our inference, not a vendor statement
Affected range stops below 88.0, so it looks safe — our inference, not a vendor statement
v < 78.10
Affected range stops below 78.10, so it looks safe — our inference, not a vendor statement
v < 78.10
Affected range stops below 78.10, so it looks safe — our inference, not a vendor statement
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
References (4)
x_refsource_MISCIssue TrackingPermissions RequiredVendor Advisory
Source: [email protected]
https://bugzilla.mozilla.org/show_bug.cgi?id=1667456x_refsource_MISCRelease NotesVendor Advisory
Source: [email protected]
https://www.mozilla.org/security/advisories/mfsa2021-14/x_refsource_MISCRelease NotesVendor Advisory
Source: [email protected]
https://www.mozilla.org/security/advisories/mfsa2021-15/x_refsource_MISCRelease NotesVendor Advisory
Source: [email protected]
https://www.mozilla.org/security/advisories/mfsa2021-16/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-345
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