Microsoft · Wasmtime 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2 GC Heap Corruption via Tag Imports
Affects MicrosoftSource GCVE Database
Not known to be exploited · CVSS 5.9 Medium : upgrade to 49.0.2 or 48.0.4 when convenient.
Data as of 28 Oct 2026, 09:43 UTC
- Patch
- Available – fixed in 49.0.2, 48.0.4
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 22 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade wasmtime and github/bytecodealliance/wasmtime to 49.0.2 or 48.0.4.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| bytecodealliancewasmtime | Affected
| Fixed in
|
| bytecodealliancewasmtime | Affected
| Fixed in
|
crates.iogithub/bytecodealliance/wasmtimepkg:cargo/github/bytecodealliance/wasmtimeOther threats | Affected
| Fixed in
|
crates.iowasmtimepkg:cargo/wasmtimeOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
CVE-2026-115383 is a vulnerability in Wasmtime versions 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2 involving garbage collector (GC) heap corruption via tag imports. The advisory references Microsoft as the vendor but provides no detailed technical or impact information.