fast-uri is a dependency-free RFC 3986 URI parser for Node.js, used by Fastify and ajv, that added a mailto scheme parser in version 4.1.3. In versions 4.1.3 and 4.1.4, the mailto parser compares each query field name to the reserved names to, subject, and body while the name is still percent-encoded, and decodes it only when storing it as a generic header, so a percent-encoded spelling of a reserved field name is not recognized as that field at parse time but is re-emitted as the literal field name when the parsed URI is serialized. An application that validates, logs, or displays the recipient list from the first parse and then serializes the URI and sends it can silently gain an attacker-chosen recipient, and the subject and body fields can be smuggled across the same roundtrip. The issue is fixed in fast-uri 4.1.5, and users should upgrade to 4.1.5 or later. As a workaround, do not act on a mailto URI that fast-uri has re-serialized without first decoding and re-validating its recipient, subject, and body fields.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - fast-uri is a dependency-free RFC 3986 URI parser for Node.js, used by Fastify and ajv, that added a
    mailto scheme parser in version 4.1.3. In versions 4.1.3 and 4.1.4, the mailto parser compares each query
    field name to the reserved names to, subject, and body while the name is still percent-encoded, and
    decodes it only when storing it as a generic header, so a percent-encoded spelling of a reserved field
    name is not recognized as that field at parse time but is re-emitted as the literal field name when the
    parsed URI is serialized. An application that validates, logs, or displays the recipient list from the
    first parse and then serializes the URI and sends it can silently gain an attacker-chosen recipient, and
    the subject and body fields can be smuggled across the same roundtrip. The issue is fixed in fast-uri
    4.1.5, and users should upgrade to 4.1.5 or later. As a workaround, do not act on a mailto URI that fast-
    uri has re-serialized without first decoding and re-validating its recipient, subject, and body fields.
    (CVE-2026-86818)

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - fast-uri is a dependency-free RFC 3986 URI parser for Node.js, used by Fastify and ajv, that added a     mailto scheme parser in version 4.1.3. In versions 4.1.3 and 4.1.4, the mailto parser compares each query     field name to the reserved names to, subject, and body while the name is still percent-encoded, and     decodes it only when storing it as a generic header, so a percent-encoded spelling of a reserved field     name is not recognized as that field at parse time but is re-emitted as the literal field name when the     parsed URI is serialized. An application that validates, logs, or displays the recipient list from the     first parse and then serializes the URI and sends it can silently gain an attacker-chosen recipient, and     the subject and body fields can be smuggled across the same roundtrip. The issue is fixed in fast-uri     4.1.5, and users should upgrade to 4.1.5 or later. As a workaround, do not act on a mailto URI that fast-     uri has re-serialized without first decoding and re-validating its recipient, subject, and body fields.
    (CVE-2026-86818)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
471648	Chainguard: tensorflow-gpu-jupyter: security update to 2.21.0-r11	Tenable Cloud Security	Chainguard Local Security Checks	Local	medium
471648	Chainguard: tensorflow-gpu-jupyter: security update to 2.21.0-r11	Tenable Self-Hosted Container Security	Chainguard Local Security Checks	Local	medium
345871	Linux Distros Unpatched Vulnerability : CVE-2026-86818	Nessus	Misc.	Local	medium

Detections

Analytics

CVE-2026-86818

medium

Tenable Plugins

medium

medium

medium