This vulnerability arises from improperly controlled sequential memory allocation within the weixin4j library. An attacker can supply data that forces the system to allocate many memory blocks in sequence, exhausting available heap and causing the application to crash or become unresponsive. The weakness corresponds to CWE‑1325 and primarily threatens the availability of services that depend on the library.

The affected product is foxinmy weixin4j, specifically modules located in weixin4j-base/src/main/java/com/foxinmy/weixin4j/util, including CharArrayBuffer.Java and ClassUtil.Java. No specific version information is provided; any deployment using the default or unpatched weixin4j code base is potentially impacted.

With a CVSS score of 6.3 the vulnerability presents moderate risk. The EPSS score is less than 1%, indicating a low current exploitation probability, and the vulnerability is not listed in the CISA KEV catalog. The likely attack vector is remote, given that malformed input can be sent over network interfaces running the library, but local use could also trigger the issue if an adversary can influence the input. The impact is limited to denial of service rather than confidentiality or integrity compromise.