Medium severity · published Jul 8, 2026
CVE-2026-58494
Wasmtime: WASI hard links bypass wasmtime-wasi's FilePerms for destination
6.5
CVSS
0.2%
EPSS
No
On KEV
Description
Wasmtime is a runtime for WebAssembly. Prior to 24.0.11, 36.0.12, 45.0.3, and 46.0.1, wasmtime-wasi hard-link creation and renaming check directory permissions but not matching FilePerms on source and destination preopens, allowing a WASI guest with a read-only source file capability to overwrite host files exposed as FilePerms::READ through wasip1, wasip2, or wasip3 filesystem interfaces. This issue is fixed in versions 24.0.11, 36.0.12, 45.0.3, and 46.0.1.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 6% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WA
wasmtime · bytecodealliance
< 24.0.11; >= 25.0.0, < 36.0.12; >= 37.0.0, < 45.0.3; >= 46.0.0, < 46.0.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-58494
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-58494
github.com
https://github.com/bytecodealliance/wasmtime/commit/5ddfd5f1ef28f2041fa07d237ad0336e167b0e0c
github.com
https://github.com/bytecodealliance/wasmtime/commit/7db94cdcf0c79cb3dfde884b534b653f2dd83367
github.com
https://github.com/bytecodealliance/wasmtime/commit/8a250aac0962ca1364b5f16525720e9d0b39edcd
github.com
https://github.com/bytecodealliance/wasmtime/commit/d3ceb56ec35f39e02496eeb4e2d9c7f4fb964d9e
github.com
https://github.com/bytecodealliance/wasmtime/releases/tag/v24.0.11
github.com
https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.12
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