Vulnerability · Published Nov 9, 2023 · Assigned by Go

CVE-2023-45283Insecure parsing of Windows paths with a \??\ prefix in path/filepath

High 7.5

In plain English

A high-severity security flaw in internal/safefilepath from Go standard library. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 3.3% (higher than 89% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)7.5High
Exploit odds (30 days)3.3%top 11.4% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official description

The filepath package does not recognize paths with a \??\ prefix as special. On Windows, a path beginning with \??\ is a Root Local Device path equivalent to a path beginning with \\?\. Paths with a \??\ prefix may be used to access arbitrary locations on the system. For example, the path \??\c:\x is equivalent to the more common path c:\x. Before fix, Clean could convert a rooted path such as \a\..\??\b into the root local device path \??\b. Clean will now convert this to .\??\b. Similarly, Join(\, ??, b) could convert a seemingly innocent sequence of path elements into the root local device path \??\b. Join will now convert this to \.\??\b. In addition, with fix, IsAbs now correctly reports paths beginning with \??\ as absolute, and VolumeName correctly reports the \??\ prefix as a volume name. UPDATE: Go 1.20.11 and Go 1.21.4 inadvertently changed the definition of the volume name in Windows paths starting with \?, resulting in filepath.Clean(\?\c:) returning \?\c: rather than \?\c:\ (among other effects). The previous behavior has been restored.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12golang-1.19no fix listedDEBIAN-CVE-2023-45283
Gostdlib1.20.11, 1.21.4GO-2023-2185
Gostdlib1.20.12, 1.21.5GO-2023-2185
Ubuntu:22.04:LTSgolang-1.17no fix listedUBUNTU-CVE-2023-45283
Ubuntu:22.04:LTSgolang-1.18no fix listedUBUNTU-CVE-2023-45283

Affected products (as reported)

VendorProductVersions
Go standard library path/filepath 0 – before 1.20.111.21.0-0 – before 1.21.4
Go standard library internal/safefilepath 0 – before 1.20.111.21.0-0 – before 1.21.4
Go standard library path/filepath 1.20.11 – before 1.20.121.21.4 – before 1.21.5

References