CVE-2021-29923

    Dashboard / Vulnerabilities / CVE-2021-29923

    CVE-2021-29923

    Published: 7 Aug 2021Last Modified: 8 Jul 2026

    Summary:

    Details: 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.

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

    Affected packages

    Package

    Name:

    Purl:

    Affected ranges

    Type: GIT

    Events:

    Introduced- 0
    Fixed -ec5170397c724a8ae440b2bc529f857c86f0e6b1

    Affected versions

    go1.17rc2

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    CVE-2021-29923 | CVE-DB