CVE-2018-5382 Bouncy Castle BKS-V1 keystore files vulnerable to trivial hash collisions
Attackers can compromise BKS keystore integrity due to weak 16-bit HMAC, allowing unauthorized modification of stored keys.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2018-5382?
CVE-2018-5382 is a medium-severity vulnerability in Bouncycastle Bc-Java, published on 16 Apr 2018. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2018-5382?
2 open source packages ship an affected version, including org.bouncycastle:bcprov-jdk15on. It affects 3 products.
| Package | Affected | Fixed in |
|---|---|---|
org.bouncycastle:bcprov-jdk15on Maven | All versions | 1.50 |
org.bouncycastle:bcprov-jdk15on Maven | All versions | 1.50 |
Products include Bouncycastle Bc-Java, Redhat Satellite, Redhat Satellite Capsule.
How do I fix CVE-2018-5382?
Upgrade org.bouncycastle:bcprov-jdk15on to 1.50 or later.
Is CVE-2018-5382 being exploited?
There is no known exploitation of CVE-2018-5382 in the wild and no public exploit code.
Other vulnerabilities in Bouncycastle Bc-Java
- CVE-2007-6721 Legion of the Bouncy Castle Java Cryptography API Bleichenbacher Oracle Vulnerability
- CVE-2018-1000613 Deserialization of Untrusted Data in Bouncy castle
- CVE-2026-58062 Stapled OCSP response accepted without binding to the checked certificate
- CVE-2026-59638 JSSE hostname verifier CN-fallback enabled by default despite documented opt-in
- CVE-2026-59650 MTI/A0 DH agreement exponentiates unvalidated peer value
Sources
Also known as DEBIAN-CVE-2018-5382, GHSA-8477-3v39-ggpm.