Signature validation bypass via altered PDF acceptance
Published Jun 4, 2020 · Updated Aug 5, 2024
Signature validation bypass in Foxit Reader and PhantomPDF before 9.5 allows remote attackers to present altered PDFs as valid. The validator accepts malicious post-signature PDF revisions or non-standard signatures without invalidating the signature and returns an incorrect result. The impact occurs when a recipient or automated workflow trusts that result, allowing attacker-controlled document content to be mistaken for content approved by the signer.
Summary
What happened
Signature validation bypass in Foxit Reader and PhantomPDF before 9.5 allows remote attackers to present altered PDFs as valid. The validator accepts malicious post-signature PDF revisions or non-standard signatures without invalidating the signature and returns an incorrect result. The impact occurs when a recipient or automated workflow trusts that result, allowing attacker-controlled document content to be mistaken for content approved by the signer.
The record
- CVE
- CVE-2019-20837
- Published
- Jun 4, 2020
- Updated
- Aug 5, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-347, CAPEC-475, T1036
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 4, 2020CVE publishedPublication date reported by the CVE source.
- Aug 5, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
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
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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