# CVE-2026-119131: Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Host Panic via wasi-http

Status: published. Published: 2026-10-29. Updated: 2026-11-04.

Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 contains a denial of service vulnerability in wasmtime-wasi-http that lets guests crash the host by sending long request URLs. Guests can use set-path-with-query with a '?' after byte 65535, overflowing a u16 index in the http crate and triggering a host panic.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- bytecodealliance / wasmtime (wasmtime-wasi-http): ≥ 46.0.0; < 48.0.6 (affected, semver); 48.0.6 (unaffected, semver); ≥ 49.0.0; < 49.0.3 (affected, semver); 49.0.3 (unaffected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 6.9 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 5.3 (medium); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: 0.30% as of 2026-11-03; percentile 23.29%

- SSVC: exploitation none; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-190

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-w36r-2hch-9xp9 (CNA: VulnCheck; vendor-advisory)

- https://www.vulncheck.com/advisories/wasmtime-46.0.0-before-48.0.6-and-49.0.0-before-49.0.3-host-panic-via-wasi-http (CNA: VulnCheck; third-party-advisory)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-119131; retrieved 2026-11-04; source updated 2026-11-04

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-119131; retrieved 2026-11-04; source updated Not reported

Revision: c835aa918ec90d6834279390dbe1da026e02070c1a24aff2faf3d06e9e97f052

Canonical: https://y2.dev/cve/CVE-2026-119131

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