Wasmtime doesn't fully sandbox all the Windows device filenames
Exact source revision recorded 24 Oct 2026 13:19:54 UTC. It does not establish the source's current position. Latest evidence.
osv · GHSA-c2f5-jxjv-2hh8
Published### Impact Wasmtime's filesystem sandbox implementation on Windows blocks access to special device filenames such as "COM1", "COM2", "LPT0", "LPT1", and so on, however it did not block access to the special device filenames which use superscript digits, such as "COM¹", "COM²", "LPT⁰", "LPT¹", and so on. Untrusted Wasm programs that are given access to any filesystem directory could bypass the sandbox and access devices through those special device filenames with superscript digits, and through them gain access peripheral devices connected to the computer, or network resources mapped to those devices. This can include modems, printers, network printers, and any other device connected to a serial or parallel port, including emulated USB serial ports. ### Patches Patch releases for Wasmtime have been issued as 24.0.2, 25.0.3, and 26.0.1. Users of Wasmtime 23.0.x and prior are recommended to upgrade to one of these patched versions. ### Workarounds There are no known workarounds for this issue. Affected Windows users are recommended to upgrade. ### References - [Microsoft's documentation](https://learn.microsoft.com/en-us/windows/win32/fileio/naming-a-file#naming-conventions) of the special device filenames - [ISO-8859-1](https://en.wikipedia.org/wiki/ISO/IEC_8859-1) - [The original PR reporting the issue](https://github.com/bytecodealliance/cap-std/pull/371)
- Source published
- 5 Nov 2024 22:18:49 UTC
- Source modified
- 10 Sep 2026 03:50:20 UTC
- Observed here
- 24 Oct 2026 13:19:54 UTC
- Source terms
- GitHub Advisory Database · CC-BY-4.0
Original source record · Cite this exact observation · Complete original publisher JSON
This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.
CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
Publisher rating · LOW