Vulnerabilities > CVE-2023-34454 - Integer Overflow or Wraparound vulnerability in Xerial Snappy-Java

047910
CVSS 7.5 - HIGH
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
NONE
Integrity impact
NONE
Availability impact
HIGH
network
low complexity
xerial
CWE-190

Summary

snappy-java is a fast compressor/decompressor for Java. Due to unchecked multiplications, an integer overflow may occur in versions prior to 1.1.10.1, causing an unrecoverable fatal error. The function `compress(char[] input)` in the file `Snappy.java` receives an array of characters and compresses it. It does so by multiplying the length by 2 and passing it to the rawCompress` function. Since the length is not tested, the multiplication by two can cause an integer overflow and become negative. The rawCompress function then uses the received length and passes it to the natively compiled maxCompressedLength function, using the returned value to allocate a byte array. Since the maxCompressedLength function treats the length as an unsigned integer, it doesn’t care that it is negative, and it returns a valid value, which is casted to a signed integer by the Java engine. If the result is negative, a `java.lang.NegativeArraySizeException` exception will be raised while trying to allocate the array `buf`. On the other side, if the result is positive, the `buf` array will successfully be allocated, but its size might be too small to use for the compression, causing a fatal Access Violation error. The same issue exists also when using the `compress` functions that receive double, float, int, long and short, each using a different multiplier that may cause the same issue. The issue most likely won’t occur when using a byte array, since creating a byte array of size 0x80000000 (or any other negative value) is impossible in the first place. Version 1.1.10.1 contains a patch for this issue.

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Forced Integer Overflow
    This attack forces an integer variable to go out of range. The integer variable is often used as an offset such as size of memory allocation or similarly. The attacker would typically control the value of such variable and try to get it out of range. For instance the integer in question is incremented past the maximum possible value, it may wrap to become a very small, or negative number, therefore providing a very incorrect value which can lead to unexpected behavior. At worst the attacker can execute arbitrary code.