Microsoft · Wasmtime 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2 GC Heap Corruption via try_call
Affects MicrosoftSource GCVE Database
Not known to be exploited · CVSS 6.9 Medium : upgrade to 49.0.2 or 48.0.4 when convenient.
Data as of 28 Oct 2026, 09:44 UTC
- Patch
- Available – fixed in 49.0.2, 48.0.4
CVSS:4.0/AV:N/AC:L/AT:N/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 bytecodealliance/wasmtime to 49.0.2 or 48.0.4.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| bytecodealliancewasmtime | Affected
| Fixed in
|
| bytecodealliancewasmtime | Affected
| Fixed in
|
GitHubbytecodealliance/wasmtimepkg: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-2026-115379 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 the try_call function. The vulnerability relates to use-after-free issues (CWE-416). No CVSS score or detailed impact information is provided.