What is CVE-2022-36087?

CVE-2022-36087 is a medium-severity improper input validation vulnerability in oauthlib (pip), affecting versions >= 3.1.1, < 3.2.2. It is fixed in 3.2.2. The application does not adequately validate input before processing it, allowing unexpected values to reach sensitive code paths.

How severe is CVE-2022-36087?

CVE-2022-36087 has a CVSS score of 5.7 (Medium). 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 oauthlib are affected by CVE-2022-36087?

oauthlib (pip) versions >= 3.1.1, < 3.2.2 is affected.

Is there a fix for CVE-2022-36087?

Yes. CVE-2022-36087 is fixed in 3.2.2. Upgrade to this version or later.

Is CVE-2022-36087 exploitable, and should I be worried?

Whether CVE-2022-36087 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-2022-36087 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-2022-36087?

Upgrade oauthlib to 3.2.2 or later.

CVE-2022-36087 in oauthlib

Q: How severe is CVE-2022-36087?

CVE-2022-36087 has a CVSS score of 5.7 (Medium). 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 oauthlib are affected by CVE-2022-36087?

oauthlib (pip) versions >= 3.1.1, < 3.2.2 is affected.

Q: Is there a fix for CVE-2022-36087?

Yes. CVE-2022-36087 is fixed in 3.2.2. Upgrade to this version or later.

Q: Is CVE-2022-36087 exploitable, and should I be worried?

Whether CVE-2022-36087 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-2022-36087 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-2022-36087?

Upgrade oauthlib to 3.2.2 or later.

Summary

OAuthLib vulnerable to DoS when attacker provides malicious IPV6 URI

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?

The redirect_uri can be verified in web toolkit (i.e bottle-oauthlib, django-oauth-toolkit, ...) before oauthlib is called. A sample check if : is present to reject the request can prevent the DoS, assuming no port or IPv6 is fundamentally required.

References

Attack Vector:

Attacker providing malicious redirect uri:
https://github.com/oauthlib/oauthlib/blob/d4bafd9f1d0eba3766e933b1ac598cbbf37b8914/oauthlib/oauth2/rfc6749/grant_types/base.py#L232
Vulnerable uri_validate functions:
https://github.com/oauthlib/oauthlib/blob/2b8a44855a51ad5a5b0c348a08c2564a2e197ea2/oauthlib/uri_validate.py

PoC

is_absolute_uri("http://[:::::::::::::::::::::::::::::::::::::::]/path")

Acknowledgement

Special thanks to Sebastian Chnelik - PyUp.io

Impact

Attacker providing malicious redirect uri can cause DoS to oauthlib's web application.
Attacker can also leverage usage of uri_validate functions depending where it is used.

What kind of vulnerability is it? Who is impacted?

Oauthlib applications using OAuth2.0 provider support or use directly uri_validate function.

The application does not adequately validate input before processing it, allowing unexpected values to reach sensitive code paths. Typical impact: varies by context: data corruption, logic bypass, or denial of service.

CVE-2022-36087 has a CVSS score of 5.7 (Medium). The vector is network-reachable, low privileges required, and user interaction required. 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 (3.2.2); upgrading removes the vulnerable code path.

Affected versions

oauthlib (>= 3.1.1, < 3.2.2)

Security releases

oauthlib → 3.2.2 (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.

Already deployed Kodem?

See it in your environment New to Kodem? Get a demo →

Remediation advice

Has the problem been patched? What versions should users upgrade to?

Issue fixed in 3.2.2 release.

Frequently Asked Questions

What is CVE-2022-36087? CVE-2022-36087 is a medium-severity improper input validation vulnerability in oauthlib (pip), affecting versions >= 3.1.1, < 3.2.2. It is fixed in 3.2.2. The application does not adequately validate input before processing it, allowing unexpected values to reach sensitive code paths.
How severe is CVE-2022-36087? CVE-2022-36087 has a CVSS score of 5.7 (Medium). 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 oauthlib are affected by CVE-2022-36087? oauthlib (pip) versions >= 3.1.1, < 3.2.2 is affected.
Is there a fix for CVE-2022-36087? Yes. CVE-2022-36087 is fixed in 3.2.2. Upgrade to this version or later.
Is CVE-2022-36087 exploitable, and should I be worried? Whether CVE-2022-36087 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-2022-36087 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-2022-36087? Upgrade oauthlib to 3.2.2 or later.