Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
CWE-589 Variant Incomplete
Call to Non-ubiquitous API
This vulnerability occurs when software relies on an operating system function that isn't available on all versions of the target platform. This can cause crashes, unexpected behavior, or security…
Definition
What is CWE-589?
This vulnerability occurs when software relies on an operating system function that isn't available on all versions of the target platform. This can cause crashes, unexpected behavior, or security failures when the software runs in an environment where the API is missing.
Operating systems evolve, and security-critical APIs are not universally present. Functions introduced in newer OS versions will be absent in older ones, while deprecated functions may be removed entirely. If your application unconditionally calls these non-ubiquitous APIs, it can lead to portability issues, sudden crashes (denial of service), or inconsistent security enforcement across different user environments.
To avoid this, developers should proactively check for API availability at runtime or during compilation, using feature detection or version checks. Alternatively, provide fallback mechanisms or clear minimum system requirements. Relying on deprecated security APIs is especially risky, as they are often phased out due to known weaknesses, leaving your application vulnerable even on platforms where they still exist.
Real-world impact
Real-world CVEs caused by CWE-589
No public CVE references are linked to this CWE in MITRE's catalog yet.
How attackers exploit it
Step-by-step attacker path
- 1
Identify a code path that handles untrusted input without validation.
- 2
Craft a payload that exercises the unsafe behavior — injection, traversal, overflow, or logic abuse.
- 3
Deliver the payload through a normal request and observe the application's reaction.
- 4
Iterate until the response leaks data, executes attacker code, or escalates privileges.
Vulnerable code example
Vulnerable pseudo
MITRE has not published a code example for this CWE. The pattern below is illustrative — see Resources for canonical references.
// Example pattern — see MITRE for the canonical references.
function handleRequest(input) {
// Untrusted input flows directly into the sensitive sink.
return executeUnsafe(input);
} Secure code example
Secure pseudo
// Validate, sanitize, or use a safe API before reaching the sink.
function handleRequest(input) {
const safe = validateAndEscape(input);
return executeWithGuards(safe);
} What changed: the unsafe sink is replaced (or the input is validated/escaped) so the same payload no longer triggers the weakness.
Prevention checklist
How to prevent CWE-589
- Implementation Always test your code on any platform on which it is targeted to run on.
- Testing Test your code on the newest and oldest platform on which it is targeted to run on.
- Testing Develop a system to test for API functions that are not portable.
Detection signals
How to detect CWE-589
CWE-589
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Frequently asked questions What is CWE-589?
How serious is CWE-589?
What languages or platforms are affected by CWE-589?
How can I prevent CWE-589?
How does Plexicus detect and fix CWE-589?
Where can I learn more about CWE-589?
Frequently asked questions
What is CWE-589?
This vulnerability occurs when software relies on an operating system function that isn't available on all versions of the target platform. This can cause crashes, unexpected behavior, or security failures when the software runs in an environment where the API is missing.
How serious is CWE-589?
MITRE has not published a likelihood-of-exploit rating for this weakness. Treat it as medium-impact until your threat model proves otherwise.
What languages or platforms are affected by CWE-589?
MITRE has not specified affected platforms for this CWE — it can apply across most application stacks.
How can I prevent CWE-589?
Always test your code on any platform on which it is targeted to run on. Test your code on the newest and oldest platform on which it is targeted to run on.
How does Plexicus detect and fix CWE-589?
Plexicus's SAST engine matches the data-flow signature for CWE-589 on every commit. When a match is found, our Codex Remedium agent opens a fix PR with the corrected code, tests, and a one-line summary for the reviewer.
Where can I learn more about CWE-589?
MITRE publishes the canonical definition at https://cwe.mitre.org/data/definitions/589.html. You can also reference OWASP and NIST documentation for adjacent guidance.
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Ready to validate what matters?
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