CVE-2022-41720: high-severity vulnerability in Go standard library net/http
Restricted file access on Windows in os and net/http
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 1.3%
On Windows, restricted files can be accessed via os.DirFS and http.Dir. The os.DirFS function and http.Dir type provide access to a tree of files rooted at a given directory. These functions permit access to Windows device files under that root. For example, os.DirFS("C:/tmp").Open("COM1") opens the COM1 device. Both os.DirFS and http.Dir only provide read-only filesystem access. In addition, on Windows, an os.DirFS for the directory (the root of the current drive) can permit a maliciously crafted path to escape from the drive and access any path on the system. With fix applied, the behavior of os.DirFS("") has changed. Previously, an empty root was treated equivalently to "/", so os.DirFS("").Open("tmp") would open the path "/tmp". This now returns an error.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Related CVEs — Go standard library net/http
In the same product, most dangerous first.
CVE-2023-45288HIGHHTTP/2 CONTINUATION flood in net/httpEPSS 89.5%CVE-2022-41717—Excessive memory growth in net/http and golang.org/x/net/http2EPSS 6.1%CVE-2022-41723HIGHDenial of service via crafted HTTP/2 stream in net/http and golang.org/x/netEPSS 4.6%CVE-2023-39325—HTTP/2 rapid reset can cause excessive work in net/httpEPSS 3.8%CVE-2026-39821CRITICALInvoking failure to reject ASCII-only Punycode-encoded labels in golang.org/x/net/idnaEPSS 1.8%CVE-2022-1705MEDIUMImproper sanitization of Transfer-Encoding headers in net/httpEPSS 1.5%