CVEsbytecodeallianceCVE-2026-119143Published Oct 29, 15:58 · Updated Oct 29, 15:58 UTC
4.8
MediumCVSS 3.1 · from VulnCheck
CVE-2026-119143

Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Panic via Zero-Length Stream Writes

wasmtime · CWE-129 · CWE-129
Affectedwasmtime
FixUpdate to 48.0.6, 49.0.3 or newer
PublishedOct 29, 15:58 · VulnCheck
ScoredOct 29 · 4.8 · VulnCheck
Exploit code publicNone known · checked 21:18 UTC
ExploitedNone known · CISA KEV checked 22:10 UTC

What we know

No known exploitation. CISA KEV, checked 22:10 UTC.
No public exploit code known. Exploit-DB, Metasploit, Nuclei, checked 21:18 UTC.
An attacker needs network access and an account. CVSS: network, low privileges.
It only works under certain conditions, which makes it harder to pull off. CVSS: high attack complexity.
Someone has to open, click or run something first. CVSS: user interaction required.
A successful attack can take the service down. CVSS impact.

Description

Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 contains a denial of service vulnerability that allows guest code to trigger a host panic through out-of-bounds zero-length stream operations. Malicious guests can perform zero-length component model stream reads or writes with unvalidated addresses, causing Direct{Source,Destination}::remaining to panic and crash WASIp3 embedders.

From VulnCheck

Affected and fixed versions

ProductAffectedFixed inwasmtime46.0.0 – before 48.0.648.0.6wasmtimeNot affected48.0.6wasmtime49.0.0 – before 49.0.349.0.3wasmtimeNot affected49.0.3

Exploit code

Exploit-DBnone knownMetasploitnone knownNucleinone known

References

GitHub Security Advisory (GHSA-93g3-36p8-x2gc) · github.comvendor advisoryVulnCheck Advisory: Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Panic via Zero-Length Stream Writes · vulncheck.comthird party advisory

Other CVEs in wasmtime

All 77 →
4.8Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Host Panic via call_async Drop · CVE-2026-119142Oct 295.3Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Host Panic via realloc · CVE-2026-119141Oct 294.8Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Host Panic via thread.yield · CVE-2026-119140Oct 29