Summary
aircompressor Snappy and LZ4 Java-based decompressor implementation can leak information from reused output buffer
Incorrect handling of malformed data in Java-based decompressor implementations for Snappy and LZ4 allows remote attackers to read previous buffer contents via crafted compressed input. In applications where the output buffer is reused without being cleared, this may lead to disclosure of sensitive data.
Details
With certain crafted compressed inputs, elements from the output buffer can end up in the uncompressed output. This is relevant for applications that reuse the same output buffer to uncompress multiple inputs. This can be the case of a web server that allocates a fix-sized buffer for performance purposes. This is similar to GHSA-cmp6-m4wj-q63q.
Mitigation
The vulnerability is fixed in release 3.4 and 2.0.3. However, it can be mitigated by either:
- Avoiding reuse of the decompression buffer across calls
- Clearing the decompression buffer before a call to decompress data
Impact
Applications using aircompressor as described above may leak sensitive information to external unauthorized attackers.
A read operation accesses a memory location beyond the intended buffer boundary. Typical impact: sensitive data disclosure or crash.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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io.airlift:aircompressor-v3 to 3.4 or later; io.airlift:aircompressor to 2.0.3 or later
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2025-67721? CVE-2025-67721 is a high-severity out-of-bounds read vulnerability in io.airlift:aircompressor-v3 (maven), affecting versions < 3.4. It is fixed in 3.4, 2.0.3. A read operation accesses a memory location beyond the intended buffer boundary.
- Which packages are affected by CVE-2025-67721?
io.airlift:aircompressor-v3(maven) (versions < 3.4)io.airlift:aircompressor(maven) (versions < 2.0.3)
- Is there a fix for CVE-2025-67721? Yes. CVE-2025-67721 is fixed in 3.4, 2.0.3. Upgrade to this version or later.
- Is CVE-2025-67721 exploitable, and should I be worried? Whether CVE-2025-67721 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2025-67721 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2025-67721?
- Upgrade
io.airlift:aircompressor-v3to 3.4 or later - Upgrade
io.airlift:aircompressorto 2.0.3 or later
- Upgrade