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, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

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

Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.

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 1.0%, placing it in the 64th 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 October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹

🐹 Go

Not in CISA KEV

MEDIUM severity

CVE-2023-40023 — yaklang

MEDIUMFix: yaklang/yaklang#295

CVE-2023-40023 is a medium-severity (CVSS 6.5) Information Exposure vulnerability in github.com/yaklang/yaklang. A fix is available for github.com/yaklang/yaklang — see the affected versions and patch details below.

Yaklang Plugin's Fuzztag Component Allows Unauthorized Local File Reading

Also known asGHSA-xvhg-w6qc-m3qqGO-2023-2011

Published

Aug 14, 2023

Updated

Oct 28, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 5, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2023-40023.

EPSS Exploitation Probability

via FIRST.org ↗

1.0%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs64th percentile — riskier than 64% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

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

Impact

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.

Patches

The vulnerability has been addressed and patched. Users are advised to upgrade to Yak Engine version 1.2.4-sp1 immediately. The patch can be viewed and reviewed at this PR: https://github.com/yaklang/yaklang/pull/295，https://github.com/yaklang/yaklang/pull/296

Workarounds

Currently, the most effective solution is to upgrade to the patched version of Yak Engine (1.2.4-sp1). Users are also advised to avoid exposing vulnerable versions to untrusted input and to closely monitor any unexpected server behavior until they can upgrade.

References

For more details on the vulnerability and the corresponding patch, please visit the following link:

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/yaklang/yaklang`	all versions	1.2.4-sp2`go get github.com/yaklang/yaklang@v1.2.4-sp2`

Affected Products

1 product · 26 configurations

Application

yaklangyaklang

5 versions

1.2.01.2.11.2.21.2.31.2.4

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, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
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
Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.

Frequently Asked Questions

### Impact 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. ### Patches The vulnerability has been addressed and patched. Users are advised to upgrade to Yak Engine version 1.2.4-sp1 immediately. The patch can be viewed and review