CVE-2021-29923

Public Exploit

Description

Go before 1.17 does not properly consider extraneous zero characters at the beginning of an IP address octet, which (in some situations) allows attackers to bypass access control that is based on IP addresses, because of unexpected octal interpretation. This affects net.ParseIP and net.ParseCIDR.

7.5

CVSS

Severity: High

CVSS 3.1 •

CVSS 2.0 •

EPSS 0.08%

Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org Vendor Advisory golang.org

Affected: n/a n/a

References

Link	Tags
https://golang.org/pkg/net/#ParseCIDR	vendor advisory
https://www.oracle.com/security-alerts/cpujan2022.html	third party advisory patch
https://defcon.org/html/defcon-29/dc-29-speakers.html#kaoudis	third party advisory
https://github.com/golang/go/issues/43389	third party advisory issue tracking
https://github.com/golang/go/issues/30999	third party advisory issue tracking exploit
https://go-review.googlesource.com/c/go/+/325829/	third party advisory patch
https://github.com/sickcodes/security/blob/master/advisories/SICK-2021-016.md	third party advisory exploit
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4CHKSFMHZVOBCZSSVRE3UEYNKARTBMTM/	vendor advisory
https://security.gentoo.org/glsa/202208-02	third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-29923?: CVE-2021-29923 has been scored as a high severity vulnerability.
How to fix CVE-2021-29923?: To fix CVE-2021-29923, 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-2021-29923 being actively exploited in the wild?: It is possible that CVE-2021-29923 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.

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