CVE-2021-40839

Description

The rencode package through 1.0.6 for Python allows an infinite loop in typecode decoding (such as via ;\x2f\x7f), enabling a remote attack that consumes CPU and memory.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 13.84% Top 10%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/aresch/rencode/pull/29 third party advisory patch
https://seclists.org/fulldisclosure/2021/Sep/16 third party advisory mailing list
https://github.com/aresch/rencode/commit/572ff74586d9b1daab904c6f7f7009ce0143bb75 third party advisory patch
https://pypi.org/project/rencode/#history third party advisory
https://security.netapp.com/advisory/ntap-20211008-0001/ third party advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BMVQRPDVSVZNGGX57CFKCYT3DEYO4QB6/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MCLETLGVM5DBX6QNHQFW6TWGO5T3DENY/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-40839?
CVE-2021-40839 has been scored as a high severity vulnerability.
How to fix CVE-2021-40839?
To fix CVE-2021-40839, 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-2021-40839 being actively exploited in the wild?
It is possible that CVE-2021-40839 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~14% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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