CVE-2024-51745 [Low] | Security Bypass in Wasmtime

Wasmtime is a fast and secure runtime for WebAssembly. 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. 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. There are no known workarounds for this issue. Affected Windows users are recommended to upgrade.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.22%	0.81%	+0.59%
2	2026-06-10	0.30%	0.22%	-0.08%
3	2026-03-27	—	0.30%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.22%

0.81%

+0.59%

2026-06-10

0.30%

0.22%

-0.08%

2026-03-27

—

0.30%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
2.3	4.0	LOW	`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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network. Attack complexity (AC:L) Exploitation conditions are straightforward and stable. Attack requirements (AT:P) Additional preconditions must be present for exploitation. Privileges required (PR:L) Low privileges are required. User interaction (UI:N) No user interaction is required. Vulnerable system confidentiality impact (VC:L) Limited confidentiality impact on the vulnerable system. Vulnerable system integrity impact (VI:L) Limited integrity impact on the vulnerable system. Vulnerable system availability impact (VA:L) Limited availability impact on the vulnerable system. Subsequent system confidentiality impact (SC:N) No confidentiality impact on subsequent systems. Subsequent system integrity impact (SI:N) No integrity impact on subsequent systems. Subsequent system availability impact (SA:N) No availability impact on subsequent systems. Exploit maturity (threat) (E:X) Not defined: no reliable threat intelligence; scoring assumes the worst case (equivalent to Attacked). Confidentiality requirement (CR:X) Not defined: insufficient information; scoring treats this like High (worst case). Integrity requirement (IR:X) Not defined: insufficient information; scoring treats this like High (worst case). Availability requirement (AR:X) Not defined: insufficient information; scoring treats this like High (worst case). Modified attack vector (MAV:X) Not defined: scoring uses the Base Attack Vector (AV). Modified attack complexity (MAC:X) Not defined: scoring uses the Base Attack Complexity (AC). Modified attack requirements (MAT:X) Not defined: scoring uses the Base Attack Requirements (AT). Modified privileges required (MPR:X) Not defined: scoring uses the Base Privileges Required (PR). Modified user interaction (MUI:X) Not defined: scoring uses the Base User Interaction (UI). Modified vulnerable system confidentiality impact (MVC:X) Not defined: scoring uses the Base VC metric. Modified vulnerable system integrity impact (MVI:X) Not defined: scoring uses the Base VI metric. Modified vulnerable system availability impact (MVA:X) Not defined: scoring uses the Base VA metric. Modified subsequent system confidentiality impact (MSC:X) Not defined: scoring uses the Base SC metric. Modified subsequent system integrity impact (MSI:X) Not defined: scoring uses the Base SI metric. Modified subsequent system availability impact (MSA:X) Not defined: scoring uses the Base SA metric. Safety (supplemental) (S:X) Not evaluated. Automatable (supplemental) (AU:X) Not evaluated. Recovery (supplemental) (R:X) Not evaluated. Value density (supplemental) (V:X) Not evaluated. Vulnerability response effort (supplemental) (RE:X) Not evaluated. Provider urgency (supplemental) (U:X) Not evaluated.	—	—	[email protected]
10.0	3.1	CRITICAL	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:C) Breaking this can reach past the original component and bite other resources—bigger blast radius. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	3.9	6.0	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

2.3

4.0

LOW

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L): Exploitation conditions are straightforward and stable.
Attack requirements (AT:P): Additional preconditions must be present for exploitation.
Privileges required (PR:L): Low privileges are required.
User interaction (UI:N): No user interaction is required.
Vulnerable system confidentiality impact (VC:L): Limited confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:L): Limited integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:L): Limited availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N): No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N): No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N): No availability impact on subsequent systems.
Exploit maturity (threat) (E:X): Not defined: no reliable threat intelligence; scoring assumes the worst case (equivalent to Attacked).
Confidentiality requirement (CR:X): Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X): Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X): Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X): Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X): Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X): Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X): Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X): Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X): Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X): Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X): Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X): Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X): Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X): Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X): Not evaluated.
Automatable (supplemental) (AU:X): Not evaluated.
Recovery (supplemental) (R:X): Not evaluated.
Value density (supplemental) (V:X): Not evaluated.
Vulnerability response effort (supplemental) (RE:X): Not evaluated.
Provider urgency (supplemental) (U:X): Not evaluated.

—

[email protected]

10.0

3.1

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N): No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C): Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

3.9

6.0

[email protected]

OS Trackers for CVE-2024-51745

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2024-51745 not yet assigned priority: Debian including 1 source packages (rust-wasmtime), 3 status rows across 3 suites (forky, sid, trixie): resolved 3.	https://security-tracker.debian.org/tracker/CVE-2024-51745
`redhat`	low	—	https://access.redhat.com/security/cve/CVE-2024-51745
`ubuntu`	medium	CVE-2024-51745 medium priority: Ubuntu including 1 source packages (rust-wasmtime), 5 status rows across 5 suites (focal, jammy, noble, oracular, upstream): DNE 2, not-affected 2, needs-triage 1.	https://ubuntu.com/security/CVE-2024-51745

Affected software / configurations for CVE-2024-51745

Vendor	Product	Version	Raw CPE
bytecodealliance	wasmtime	< 24.0.2	cpe:2.3:a:bytecodealliance:wasmtime::::::rust::*
bytecodealliance	wasmtime	25.0.0	cpe:2.3:a:bytecodealliance:wasmtime:25.0.0:::::rust::
bytecodealliance	wasmtime	25.0.1	cpe:2.3:a:bytecodealliance:wasmtime:25.0.1:::::rust::
bytecodealliance	wasmtime	25.0.2	cpe:2.3:a:bytecodealliance:wasmtime:25.0.2:::::rust::
bytecodealliance	wasmtime	26.0.0	cpe:2.3:a:bytecodealliance:wasmtime:26.0.0:::::rust::

References for CVE-2024-51745

URL	Tags
https://en.wikipedia.org/wiki/ISO/IEC_8859-1	Product
https://github.com/bytecodealliance/cap-std/pull/371	Patch
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-c2f5-jxjv-2hh8	Vendor Advisory
https://learn.microsoft.com/en-us/windows/win32/fileio/naming-a-file#naming-conventions	Product

URL

CVE-2024-51745 | Wasmtime doesn't fully sandbox all the Windows device filenames

Exploit prediction scoring system (EPSS) score for CVE-2024-51745

Common vulnerability scoring system (CVSS) metrics for CVE-2024-51745

Weakness enumeration for CVE-2024-51745

GitHub Security Advisory for CVE-2024-51745

OS Trackers for CVE-2024-51745

Affected software / configurations for CVE-2024-51745

References for CVE-2024-51745