Description
Vulnerable jsrsasign will accept RSA signature with improper PKCS#1.5 padding. Decoded RSA signature value consists following form: 01(ff...(8 or more ffs)...ff)00[ASN.1 OF DigestInfo] Its byte length must be the same as RSA key length, however such checking was not sufficient.
To make crafted message for practical attack is very hard.
Recommendation
Update the jsrsasign package to the latest compatible version. Followings are version details:
- Affected version(s): < 10.2.0
- Patched version(s): 10.2.0
References
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Start a free scanRelated Issues
- RSA-PSS signature validation vulnerability by prepending zeros in jsrsasign - CVE-2020-14968
- ECDSA signature validation vulnerability by accepting wrong ASN.1 encoding in jsrsasign - CVE-2020-14966
- JWS and JWT signature validation vulnerability with special characters - CVE-2022-25898
- RSA PKCS#1 decryption vulnerability with prepending zeros in jsrsasign - CVE-2020-14967
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See something that needs correcting? Let us knowUpdated September 11, 2023