ECDSA Signature Verification Flaw in Crypt::Perl by FGasper
CVE-2020-13895

8.8HIGH

Key Information:

Vendor

P5-crypt-perl Project

Status
P5-crypt-perl
Vendor
CVE Published:
7 June 2020

What is CVE-2020-13895?

The Crypt::Perl module (p5-Crypt-Perl) prior to version 0.32 suffers from an issue in the Crypt::Perl::ECDSA function, where it fails to properly verify ECDSA signatures under specific conditions. This vulnerability arises when the r and s values are small, particularly when s equals 1, while utilizing the secp256r1 (also known as prime256v1) curve. An attacker can exploit this flaw by manipulating public r and s values to potentially guess the outcome of signature verifications, potentially compromising the integrity of cryptographic operations.

References

https://github.com/FGasper/p5-Crypt-Perl/issues/14
x_refsource_MISC
https://github.com/FGasper/p5-Crypt-Perl/commit/f960ce755...
x_refsource_MISC

CVSS V3.1

Score:
8.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.