CVE-2021-23253Network attack vector

Address-bar spoofing via left-aligned long domains

Published Jan 11, 2021 · Updated Aug 3, 2024

Address-bar spoofing in Opera Mini for Android before 53.1 allows remote attackers to conceal a malicious domain with a long URL. The address field left-aligns long URLs, exposing a trusted-looking prefix while truncating the actual registrable domain beyond the screen. A victim must view the crafted URL on a phone whose screen hides the suffix, enabling site impersonation and deceptive navigation without altering page data.

CVSS severity5.3
Medium
EPSS probability0.75%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Address-bar spoofing in Opera Mini for Android before 53.1 allows remote attackers to conceal a malicious domain with a long URL. The address field left-aligns long URLs, exposing a trusted-looking prefix while truncating the actual registrable domain beyond the screen. A victim must view the crafted URL on a phone whose screen hides the suffix, enabling site impersonation and deceptive navigation without altering page data.

The record

CVE
CVE-2021-23253
Published
Jan 11, 2021
Updated
Aug 3, 2024
Vendor
Opera
Product
Opera Mini for Android
Classifications
T1036
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 11, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Below 53.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Opera · Opera Mini for Androidversion=Below 53.1

Published CVSS scores

5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:P/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.

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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

T1036Masquerading

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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