Improper Verification of Cryptographic Signature in node-forge

Impact

RSA PKCS#1 v1.5 signature verification code is lenient in checking the digest algorithm structure. This can allow a crafted structure that steals padding bytes and uses unchecked portion of the PKCS#1 encoded message to forge a signature when a low public exponent is being used.

Patches

The issue has been addressed in node-forge 1.3.0.

References

For more information, please see
“Bleichenbacher’s RSA signature forgery based on implementation error”
by Hal Finney.

For more information

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