What is GHSA-9Q5J-JM53-V7VR?

GHSA-9Q5J-JM53-V7VR is a critical-severity integer overflow or wraparound vulnerability in lz4-sys (rust), affecting versions < 1.9.4. It is fixed in 1.9.4. An arithmetic operation produces a value that exceeds the integer type's maximum, causing it to wrap to an unexpected small value.

How severe is GHSA-9Q5J-JM53-V7VR?

GHSA-9Q5J-JM53-V7VR has a CVSS score of 9.8 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Which versions of lz4-sys are affected by GHSA-9Q5J-JM53-V7VR?

lz4-sys (rust) versions < 1.9.4 is affected.

Is there a fix for GHSA-9Q5J-JM53-V7VR?

Yes. GHSA-9Q5J-JM53-V7VR is fixed in 1.9.4. Upgrade to this version or later.

Is GHSA-9Q5J-JM53-V7VR exploitable, and should I be worried?

Whether GHSA-9Q5J-JM53-V7VR 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.

What actually determines whether GHSA-9Q5J-JM53-V7VR 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.

GHSA-9Q5J-JM53-V7VR in lz4-sys

Q: How severe is GHSA-9Q5J-JM53-V7VR?

GHSA-9Q5J-JM53-V7VR has a CVSS score of 9.8 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Q: Which versions of lz4-sys are affected by GHSA-9Q5J-JM53-V7VR?

lz4-sys (rust) versions < 1.9.4 is affected.

Q: Is there a fix for GHSA-9Q5J-JM53-V7VR?

Yes. GHSA-9Q5J-JM53-V7VR is fixed in 1.9.4. Upgrade to this version or later.

Q: Is GHSA-9Q5J-JM53-V7VR exploitable, and should I be worried?

Whether GHSA-9Q5J-JM53-V7VR 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.

Q: What actually determines whether GHSA-9Q5J-JM53-V7VR 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.

Q: How do I fix GHSA-9Q5J-JM53-V7VR?

Upgrade lz4-sys to 1.9.4 or later.

Summary

lz4-sys vulnerable to memory corruption via issue in liblz4

lz4-sys up to v1.9.3 bundles a version of liblz4 that is vulnerable to
CVE-2021-3520.

Attackers could craft a payload that triggers an integer overflow upon
decompression, causing an out-of-bounds write.

The flaw has been corrected in version v1.9.4 of liblz4, which is included
in lz4-sys 1.9.4.

Impact

An arithmetic operation produces a value that exceeds the integer type's maximum, causing it to wrap to an unexpected small value. Typical impact: incorrect size calculations leading to heap overflows or logic errors.

GHSA-9Q5J-JM53-V7VR has a CVSS score of 9.8 (Critical). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.9.4); upgrading removes the vulnerable code path.

Affected versions

lz4-sys (< 1.9.4)

Security releases

lz4-sys → 1.9.4 (rust)

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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Remediation advice

Upgrade lz4-sys to 1.9.4 or later to resolve this vulnerability.

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is GHSA-9Q5J-JM53-V7VR? GHSA-9Q5J-JM53-V7VR is a critical-severity integer overflow or wraparound vulnerability in lz4-sys (rust), affecting versions < 1.9.4. It is fixed in 1.9.4. An arithmetic operation produces a value that exceeds the integer type's maximum, causing it to wrap to an unexpected small value.
How severe is GHSA-9Q5J-JM53-V7VR? GHSA-9Q5J-JM53-V7VR has a CVSS score of 9.8 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
Which versions of lz4-sys are affected by GHSA-9Q5J-JM53-V7VR? lz4-sys (rust) versions < 1.9.4 is affected.
Is there a fix for GHSA-9Q5J-JM53-V7VR? Yes. GHSA-9Q5J-JM53-V7VR is fixed in 1.9.4. Upgrade to this version or later.
Is GHSA-9Q5J-JM53-V7VR exploitable, and should I be worried? Whether GHSA-9Q5J-JM53-V7VR 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 GHSA-9Q5J-JM53-V7VR 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 GHSA-9Q5J-JM53-V7VR? Upgrade lz4-sys to 1.9.4 or later.