What is CVE-2020-29128?

CVE-2020-29128 is a high-severity XML external entity injection (XXE) vulnerability in petl (pip), affecting versions < 1.6.8. It is fixed in 1.6.8. An XML parser processes external entity references in untrusted input, causing the server to fetch internal resources or remote URLs.

How severe is CVE-2020-29128?

CVE-2020-29128 has a CVSS score of 9.8 (High). 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 petl are affected by CVE-2020-29128?

petl (pip) versions < 1.6.8 is affected.

Is there a fix for CVE-2020-29128?

Yes. CVE-2020-29128 is fixed in 1.6.8. Upgrade to this version or later.

Is CVE-2020-29128 exploitable, and should I be worried?

Whether CVE-2020-29128 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-2020-29128 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-2020-29128 in petl

Q: How severe is CVE-2020-29128?

CVE-2020-29128 has a CVSS score of 9.8 (High). 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 petl are affected by CVE-2020-29128?

petl (pip) versions < 1.6.8 is affected.

Q: Is there a fix for CVE-2020-29128?

Yes. CVE-2020-29128 is fixed in 1.6.8. Upgrade to this version or later.

Q: Is CVE-2020-29128 exploitable, and should I be worried?

Whether CVE-2020-29128 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-2020-29128 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-2020-29128?

Upgrade petl to 1.6.8 or later.

Summary

XXE in petl

petl is a Python library that provides functions for extraction, transformation, and loading (ETL) of data.

petl before 1.68, in some configurations, allows resolution of entities in XML input.

An attacker who is able to submit XML input to an application using petl can disclose arbitrary files on the file system in the context of the user under which the application is running.

Affected Applications

Applications that:

accept attacker-supplied XML input that is processed using petl < 1.68
return the response generated by petl back to the attacker
configure lxml as the underlying XML processing library used by petl
have read privileges in filesystem files with sensitive information

Mitigation

Update to petl >= 1.68

Workarounds

Assure there is no user/external access to the application using petl
Assure your application is not using the function fromxml()

References

For more information

If you have any questions or comments about this advisory:

Add a comment in the Github issue

Thaks to Naveen Sunkavally.

Impact

Information Disclosure

An XML parser processes external entity references in untrusted input, causing the server to fetch internal resources or remote URLs. Typical impact: local file disclosure, server-side request forgery, or denial of service.

CVE-2020-29128 has a CVSS score of 9.8 (High). 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 (1.6.8); upgrading removes the vulnerable code path.

Affected versions

petl (< 1.6.8)

Security releases

petl → 1.6.8 (pip)

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 petl to 1.6.8 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-2020-29128? CVE-2020-29128 is a high-severity XML external entity injection (XXE) vulnerability in petl (pip), affecting versions < 1.6.8. It is fixed in 1.6.8. An XML parser processes external entity references in untrusted input, causing the server to fetch internal resources or remote URLs.
How severe is CVE-2020-29128? CVE-2020-29128 has a CVSS score of 9.8 (High). 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 petl are affected by CVE-2020-29128? petl (pip) versions < 1.6.8 is affected.
Is there a fix for CVE-2020-29128? Yes. CVE-2020-29128 is fixed in 1.6.8. Upgrade to this version or later.
Is CVE-2020-29128 exploitable, and should I be worried? Whether CVE-2020-29128 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-2020-29128 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-2020-29128? Upgrade petl to 1.6.8 or later.