Autofill data disclosure via page-controlled fonts
Published Dec 22, 2022 · Updated Apr 16, 2025
Information disclosure in Mozilla Firefox before 98 allows remote attackers to infer Autofill tooltip text through a crafted webpage. Autofill preview text inherits page-controlled font properties, letting crafted fonts encode rendered text characteristics that JavaScript measures indirectly. A user must visit the page and trigger an Autofill preview; the page can infer sensitive suggested values without directly reading the tooltip.
Summary
What happened
Information disclosure in Mozilla Firefox before 98 allows remote attackers to infer Autofill tooltip text through a crafted webpage. Autofill preview text inherits page-controlled font properties, letting crafted fonts encode rendered text characteristics that JavaScript measures indirectly. A user must visit the page and trigger an Autofill preview; the page can infer sensitive suggested values without directly reading the tooltip.
The record
- CVE
- CVE-2022-26382
- Published
- Dec 22, 2022
- Updated
- Apr 16, 2025
- Vendor
- Mozilla
- Product
- Firefox
- Classifications
- CWE-203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 22, 2022CVE publishedPublication date reported by the CVE source.
- Apr 16, 2025Record 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.
- Affected versionversion=unspecified <98
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
- Mozilla Bugzilla Autofill font side-channel proof of conceptproof of concept · validated
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Technologies
Your stack
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Your stack
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