GHSA-m758-wjhj-p3jq

Suggest an improvement
Source
https://github.com/advisories/GHSA-m758-wjhj-p3jq
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/04/GHSA-m758-wjhj-p3jq/GHSA-m758-wjhj-p3jq.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-m758-wjhj-p3jq
Aliases
Downstream
CGA (10)
JLSEC (1)
Published
2026-04-09T20:22:34Z
Modified
2026-09-10T03:51:02Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
  • 5.6 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVSS Calculator
Summary
Wasmtime has a possible panic when lifting `flags` component value
Details

Impact

Wasmtime contains a possible panic which can happen when a flags-typed component model value is lifted with the Val type. If bits are set outside of the set of flags the component model specifies that these bits should be ignored but Wasmtime will panic when this value is lifted. This panic only affects wasmtime's implementation of lifting into Val, not when using the flags! macro. This additionally only affects flags-typed values which are part of a WIT interface.

This has the risk of being a guest-controlled panic within the host which Wasmtime considers a DoS vector.

Patches

Wasmtime 24.0.7, 36.0.7, 42.0.2, and 43.0.1 have been issued to fix this bug. Users are recommended to update to these patched versions of Wasmtime.

Workarounds

There is no workaround for this bug if a host meets the criteria to be affected. To be affected a host must be using wasmtime::component::Val and possibly work with a flags type in the component model.

Database specific 
{
    "cwe_ids":  [
        "CWE-248"
    ],
    "github_reviewed":  true,
    "github_reviewed_at":  "2026-04-09T20:22:34Z",
    "nvd_published_at":  "2026-04-09T19:16:24Z",
    "severity":  "MODERATE"
}
References

Affected packages

crates.io / wasmtime

Package

Name
wasmtime
View open source insights on deps.dev
Purl
pkg:cargo/wasmtime

Affected ranges

Type
SEMVER
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
24.0.7

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/04/GHSA-m758-wjhj-p3jq/GHSA-m758-wjhj-p3jq.json"

crates.io / wasmtime

Package

Name
wasmtime
View open source insights on deps.dev
Purl
pkg:cargo/wasmtime

Affected ranges

Type
SEMVER
Events
Introduced
25.0.0
Fixed
36.0.7

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/04/GHSA-m758-wjhj-p3jq/GHSA-m758-wjhj-p3jq.json"

crates.io / wasmtime

Package

Name
wasmtime
View open source insights on deps.dev
Purl
pkg:cargo/wasmtime

Affected ranges

Type
SEMVER
Events
Introduced
37.0.0
Fixed
42.0.2

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/04/GHSA-m758-wjhj-p3jq/GHSA-m758-wjhj-p3jq.json"

crates.io / wasmtime

Package

Name
wasmtime
View open source insights on deps.dev
Purl
pkg:cargo/wasmtime

Affected ranges

Type
SEMVER
Events
Introduced
43.0.0
Fixed
43.0.1

Affected versions

43.*
43.0.0

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/04/GHSA-m758-wjhj-p3jq/GHSA-m758-wjhj-p3jq.json"