Vulnerabilities > CVE-2013-7372 - Cryptographic Issues vulnerability in multiple products
Attack vector
NETWORK Attack complexity
LOW Privileges required
NONE Confidentiality impact
NONE Integrity impact
PARTIAL Availability impact
NONE Summary
The engineNextBytes function in classlib/modules/security/src/main/java/common/org/apache/harmony/security/provider/crypto/SHA1PRNG_SecureRandomImpl.java in the SecureRandom implementation in Apache Harmony through 6.0M3, as used in the Java Cryptography Architecture (JCA) in Android before 4.4 and other products, when no seed is provided by the user, uses an incorrect offset value, which makes it easier for attackers to defeat cryptographic protection mechanisms by leveraging the resulting PRNG predictability, as exploited in the wild against Bitcoin wallet applications in August 2013.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Signature Spoofing by Key Recreation An attacker obtains an authoritative or reputable signer's private signature key by exploiting a cryptographic weakness in the signature algorithm or pseudorandom number generation and then uses this key to forge signatures from the original signer to mislead a victim into performing actions that benefit the attacker.
References
- http://android-developers.blogspot.com.au/2013/08/some-securerandom-thoughts.html
- http://www.nds.rub.de/media/nds/veroeffentlichungen/2013/03/25/paper_2.pdf
- https://android.googlesource.com/platform/libcore/+/kitkat-release/luni/src/main/java/org/apache/harmony/security/provider/crypto/SHA1PRNG_SecureRandomImpl.java
- https://bitcoin.org/en/alert/2013-08-11-android