CVE-2020-26939: In Legion of the Bouncy Castle BC before 1.61 and BC-FJA before 1.0.1.2, attackers can obtain sensitive information about a private exponent because of…

PriorityP424medium5.3CVSS 3.1

AVNACLPRNUINSUCLINAN

EPSS

0.91%

56.1th percentile

In Legion of the Bouncy Castle BC before 1.61 and BC-FJA before 1.0.1.2, attackers can obtain sensitive information about a private exponent because of Observable Differences in Behavior to Error Inputs. This occurs in org.bouncycastle.crypto.encodings.OAEPEncoding. Sending invalid ciphertext that decrypts to a short payload in the OAEP Decoder could result in the throwing of an early exception, potentially leaking some information about the private exponent of the RSA private key performing the encryption.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
bouncycastle	fips_java_api	< 1.0.1.2	1.0.1.2
bouncycastle	legion-of-the-bouncy-castle	< 1.61	1.61
debian	bouncycastle	< bouncycastle 1.61-1 (bookworm)	bouncycastle 1.61-1 (bookworm)

CVSS provenance

nvdv3.15.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:P/I:N/A:N

osv5.3MEDIUM

vendor_debian5.3MEDIUM

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