CVE-2025-23109Network attack vector

Address bar spoofing via long hostnames

Published Jan 11, 2025 · Updated May 20, 2026

Origin validation error in Firefox for iOS before 134 allows remote attackers to spoof the displayed address using a long hostname. Mozilla has not disclosed the affected address-bar formatting routine; the client displays a long URL so its true host is obscured. A user must open the crafted URL and trust the address display, enabling a malicious page to appear associated with a different site.

CVSS severity6.5
Medium
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Origin validation error in Firefox for iOS before 134 allows remote attackers to spoof the displayed address using a long hostname. Mozilla has not disclosed the affected address-bar formatting routine; the client displays a long URL so its true host is obscured. A user must open the crafted URL and trust the address display, enabling a malicious page to appear associated with a different site.

The record

CVE
CVE-2025-23109
Published
Jan 11, 2025
Updated
May 20, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-346, T1036.005
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 11, 2025CVE publishedPublication date reported by the CVE source.
  2. May 20, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-346Origin Validation Error
T1036.005Masquerading: Match Legitimate Resource Name or Location

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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