How severe is CVE-2023-40023?

CVE-2023-40023 has a CVSS score of 6.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2023-40023?

CVE-2023-40023 affects the following packages: github.com/yaklang/yaklang (Go). Ecosystems affected: Go.

How do I fix CVE-2023-40023?

Update github.com/yaklang/yaklang to 1.2.4-sp2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-40023 is resolved across your whole dependency graph.

How do I detect CVE-2023-40023 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/yaklang/yaklang. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2023-40023 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2023-40023?

O3 pinpoints whether CVE-2023-40023 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2023-40023 actively exploited in the wild?

No public exploit code has been indexed for CVE-2023-40023 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2023-40023?

CVE-2023-40023 has an EPSS (Exploit Prediction Scoring System) score of 0.9%, placing it in the 56th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2023-40023?

CVE-2023-40023 is classified as Information Exposure (CWE-200). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2023-40023 published, and has it been updated?

CVE-2023-40023 was published on August 14, 2023 and was last updated on April 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2023-40023: yaklang Remote Code Execution (Medium 6.5)

EPSS Exploitation Probability

via FIRST.org ↗

0.9%probability of exploitation in next 30 days

Lower Risk56th percentile+0.71%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

1 pkg affected

🐹github.com/yaklang/yaklang

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

yaklang is a programming language designed for cybersecurity. The Yak Engine has been found to contain a local file inclusion (LFI) vulnerability. This vulnerability allows attackers to include files from the server's local file system through the web application. When exploited, this can lead to the unintended exposure of sensitive data, potential remote code execution, or other security breaches. Users utilizing versions of the Yak Engine prior to 1.2.4-sp1 are impacted. This vulnerability has been patched in version 1.2.4-sp1. Users are advised to upgrade. users unable to upgrade may avoid exposing vulnerable versions to untrusted input and to closely monitor any unexpected server behavior until they can upgrade.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/yaklang/yaklang`	all versions	1.2.4-sp2

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/yaklang/yaklang. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/yaklang/yaklang to 1.2.4-sp2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-40023 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2023-40023 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2023-40023. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

yaklang is a programming language designed for cybersecurity. The Yak Engine has been found to contain a local file inclusion (LFI) vulnerability. This vulnerability allows attackers to include files from the server's local file system through the web application. When exploited, this can lead to the unintended exposure of sensitive data, potential remote code execution, or other security breaches. Users utilizing versions of the Yak Engine prior to 1.2.4-sp1 are impacted. This vulnerability has been patched in version 1.2.4-sp1. Users are advised to upgrade. users unable to upgrade may avoid

O3 Security · Impact-Aware SCA

Is CVE-2023-40023 in your dependencies?

O3 detects CVE-2023-40023 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works

CVE-2023-40023