Signature forgery via lenient PKCS#1 parsing
Published Apr 6, 2021 · Updated Aug 3, 2024
Improper RSA signature verification in phpseclib before 2.0.31 and 3.0.0 through 3.0.6 allows remote attackers to forge signatures. The RSA verification path accepts malformed PKCS#1 encoded messages instead of enforcing the complete expected structure, enabling low-public-exponent forgeries. Exploitation requires a consuming application to verify attacker-controlled messages and signatures, and the resulting impact depends on decisions that application entrusts to signature validity.
Summary
What happened
Improper RSA signature verification in phpseclib before 2.0.31 and 3.0.0 through 3.0.6 allows remote attackers to forge signatures. The RSA verification path accepts malformed PKCS#1 encoded messages instead of enforcing the complete expected structure, enabling low-public-exponent forgeries. Exploitation requires a consuming application to verify attacker-controlled messages and signatures, and the resulting impact depends on decisions that application entrusts to signature validity.
The record
- CVE
- CVE-2021-30130
- Published
- Apr 6, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-295, CWE-347
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 6, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
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Attacks
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Technologies
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