CVE-2021-29437

Account compromise by man-in-the-middle attack

Description

ScratchOAuth2 is an Oauth implementation for Scratch. Any ScratchOAuth2-related data normally accessible and modifiable by a user can be read and modified by a third party. 1. Scratch user visits 3rd party site. 2. 3rd party site asks user for Scratch username. 3. 3rd party site pretends to be user and gets login code from ScratchOAuth2. 4. 3rd party site gives code to user and instructs them to post it on their profile. 5. User posts code on their profile, not knowing it is a ScratchOAuth2 login code. 6. 3rd party site completes login with ScratchOAuth2. 7. 3rd party site has full access to anything the user could do if they directly logged in. See referenced GitHub security advisory for patch notes and workarounds.

Category

8.0
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.27%
Third-Party Advisory github.com
Affected: ScratchVerifier ScratchOAuth2
Published at:
Updated at:

References

Link Tags
https://github.com/ScratchVerifier/ScratchOAuth2/security/advisories/GHSA-gvpg-23fh-8g75 third party advisory patch
https://github.com/ScratchVerifier/ScratchOAuth2/commit/9220c2a77eda3df37a84486ad722f1ad0985d8e7 patch

Frequently Asked Questions

What is the severity of CVE-2021-29437?
CVE-2021-29437 has been scored as a high severity vulnerability.
How to fix CVE-2021-29437?
To fix CVE-2021-29437, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-29437 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-29437 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-29437?
CVE-2021-29437 affects ScratchVerifier ScratchOAuth2.
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