SB2021092225 - Security restrictions bypass in Go programming language
Published: September 22, 2021
Security Bulletin ID
SB2021092225
Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Input validation error (CVE-ID: CVE-2021-29923)
The vulnerability allows a remote attacker to bypass implemented security restrictions.
The vulnerability exists due to insufficient validation of user-supplied input in net.ParseIP and net.ParseCIDR, as the Go interpreter does not properly consider extraneous zero characters at the beginning
of an IP address octet. A remote attacker can
bypass access control that is based on IP addresses, because of
unexpected octal interpretation.
Remediation
Install update from vendor's website.
References
- https://github.com/golang/go/issues/43389
- https://github.com/golang/go/issues/30999
- https://defcon.org/html/defcon-29/dc-29-speakers.html#kaoudis
- https://github.com/sickcodes/security/blob/master/advisories/SICK-2021-016.md
- https://golang.org/pkg/net/#ParseCIDR
- https://go-review.googlesource.com/c/go/+/325829/