Is CVE-2026-121441 being exploited?

No public exploit is currently tracked.

How severe is CVE-2026-121441?

CVE-2026-121441 has a CVSS v3 severity of LOW (3.7).

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CVE-2026-121441

Description

Wasmtime before 36.0.19, 37.0.0 before 48.0.7, and 49.0.0 before 49.0.4 contains a request smuggling vulnerability in wasi-http that allows guests to set multiple conflicting content-length headers. Malicious guests can make the host send HTTP requests with conflicting content-length values to smuggle requests through servers or intermediaries that do not reject them.