This is an automated email from the ASF dual-hosted git repository.
asf-gitbox-commits pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/commons-rng.git
The following commit(s) were added to refs/heads/master by this push:
new e558d169 Document unsuitability for use in a cryptographic or security
purposes
e558d169 is described below
commit e558d169304fc2768ef6c5b4fc911badb36958b9
Author: Alex Herbert <[email protected]>
AuthorDate: Sat Aug 22 11:58:25 2026 +0100
Document unsuitability for use in a cryptographic or security purposes
---
.../apache/commons/rng/core/source32/ISAACRandom.java | 19 ++++++++++++++-----
.../org/apache/commons/rng/simple/RandomSource.java | 7 +++++++
src/changes/changes.xml | 5 +++++
3 files changed, 26 insertions(+), 5 deletions(-)
diff --git
a/commons-rng-core/src/main/java/org/apache/commons/rng/core/source32/ISAACRandom.java
b/commons-rng-core/src/main/java/org/apache/commons/rng/core/source32/ISAACRandom.java
index eff8b2e8..41593c94 100644
---
a/commons-rng-core/src/main/java/org/apache/commons/rng/core/source32/ISAACRandom.java
+++
b/commons-rng-core/src/main/java/org/apache/commons/rng/core/source32/ISAACRandom.java
@@ -21,16 +21,25 @@ import java.util.Arrays;
import org.apache.commons.rng.core.util.NumberFactory;
/**
- * A fast cryptographic pseudo-random number generator.
+ * ISAAC: a fast pseudo-random number generator.
* <p>
* ISAAC (Indirection, Shift, Accumulate, Add, and Count) generates 32-bit
* random numbers.
- * ISAAC has been designed to be cryptographically secure and is inspired
- * by RC4.
+ * ISAAC was designed by its author as a cryptographic pseudo-random number
+ * generator inspired by RC4.
* Cycles are guaranteed to be at least 2<sup>40</sup> values long, and they
* are 2<sup>8295</sup> values long on average.
- * The results are uniformly distributed, unbiased, and unpredictable unless
- * you know the seed.
+ * The results are uniformly distributed and unbiased.
+ * <p>
+ * <strong>This implementation is not suitable for cryptographic or
+ * security purposes.</strong> This library targets statistical
+ * applications: the default seeding procedure is not a cryptographically
+ * strong source of entropy, and the full internal state of the generator
+ * can be saved and restored (see
+ * {@link org.apache.commons.rng.RestorableUniformRandomProvider}), so
+ * output must be assumed to be predictable. Use
+ * {@link java.security.SecureRandom} to generate keys, tokens, session
+ * identifiers or any other security-sensitive values.
* <p>
* This code is based (with minor changes and improvements) on the original
* implementation of the algorithm by Bob Jenkins.
diff --git
a/commons-rng-simple/src/main/java/org/apache/commons/rng/simple/RandomSource.java
b/commons-rng-simple/src/main/java/org/apache/commons/rng/simple/RandomSource.java
index 0cc3f893..0749021d 100644
---
a/commons-rng-simple/src/main/java/org/apache/commons/rng/simple/RandomSource.java
+++
b/commons-rng-simple/src/main/java/org/apache/commons/rng/simple/RandomSource.java
@@ -249,6 +249,13 @@ public enum RandomSource {
* <li>Native seed type: {@code int[]}.</li>
* <li>Native seed size: 256.</li>
* </ul>
+ *
+ * <p><strong>Note:</strong> Although the ISAAC algorithm was designed by
its
+ * author as a cryptographic pseudo-random number generator, this
+ * implementation, its default seeding and its saveable state are intended
+ * for statistical applications only and are <em>not</em> suitable for
+ * cryptographic or security purposes. Use {@link
java.security.SecureRandom}
+ * for security-sensitive values.</p>
*/
ISAAC(ProviderBuilder.RandomSourceInternal.ISAAC),
/**
diff --git a/src/changes/changes.xml b/src/changes/changes.xml
index fb5ec0aa..b4aa4bb4 100644
--- a/src/changes/changes.xml
+++ b/src/changes/changes.xml
@@ -56,6 +56,11 @@ If the output is not quite correct, check for invisible
trailing spaces!
<release version="1.8" date="TBD" description="
New features, updates and bug fixes (requires Java 8).
">
+ <action dev="aherbert" type="update" due-to="Security scan, Alex
Herbert">
+ "ISAACRandom": Document unsuitability for use in a cryptographic or
security
+ purposes due to the use of a non-cryptographically strong source of
entropy for
+ seeding, and access to the internal state by save/restore
functionality.
+ </action>
<action dev="aherbert" type="update" due-to="Security scan, Alex
Herbert" issue="RNG-196">
"FastLoadedDiceRollerDiscreteSampler": Introduce a defaut alpha to
exclude
practically unobservable categories with a probability of less than
2^-53
