CVE-2018-5382 Bouncy Castle BKS-V1 keystore files vulnerable to trivial hash collisions

2012-03-2000:00:00

CWE-327

certcc

www.cve.org

4.9 Medium

AI Score

Confidence

High

0.001 Low

EPSS

Percentile

30.5%

JSON

The default BKS keystore use an HMAC that is only 16 bits long, which can allow an attacker to compromise the integrity of a BKS keystore. Bouncy Castle release 1.47 changes the BKS format to a format which uses a 160 bit HMAC instead. This applies to any BKS keystore generated prior to BC 1.47. For situations where people need to create the files for legacy reasons a specific keystore type “BKS-V1” was introduced in 1.49. It should be noted that the use of “BKS-V1” is discouraged by the library authors and should only be used where it is otherwise safe to do so, as in where the use of a 16 bit checksum for the file integrity check is not going to cause a security issue in itself.

CNA Affected

[
  {
    "product": "Bouncy Castle",
    "vendor": "Legion of the Bouncy Castle",
    "versions": [
      {
        "lessThan": "1.47",
        "status": "affected",
        "version": "all",
        "versionType": "custom"
      }
    ]
  }
]