CVE-2023-49061Public exploitNetwork attack vector

Information exfiltration via unescaped Reader Mode byline

Published Nov 21, 2023 · Updated Aug 2, 2024

HTML template injection in Reader Mode in Mozilla Firefox for iOS before 120 allows remote attackers to exfiltrate user information. %READER-BYLINE% inserts the original page's meta author value into the Reader Mode template without the HTML escaping applied to the older credits placeholder. A victim must open an attacker-controlled page in Reader Mode; injected markup can then read or transmit information exposed in that rendered context.

CVSS severity6.1
Medium
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

HTML template injection in Reader Mode in Mozilla Firefox for iOS before 120 allows remote attackers to exfiltrate user information. %READER-BYLINE% inserts the original page's meta author value into the Reader Mode template without the HTML escaping applied to the older credits placeholder. A victim must open an attacker-controlled page in Reader Mode; injected markup can then read or transmit information exposed in that rendered context.

The record

CVE
CVE-2023-49061
Published
Nov 21, 2023
Updated
Aug 2, 2024
Vendor
Mozilla
Product
Firefox for iOS
Classifications
CWE-601, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 21, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 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=unspecified <120

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mozilla · Firefox for iOSversion=unspecified <120

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/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 exploitPublished

Weakness, pattern, technique

CWE-601URL Redirection to Untrusted Site ('Open Redirect')
T1189Drive-by Compromise

Public exploit references

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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