CVE-2026-110306

Source
https://cve.org/CVERecord?id=CVE-2026-110306
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-110306.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-110306
Aliases
  • GHSA-w74x-v6f9-j3xg
Downstream
CLSA (6)
Published
2026-10-20T07:03:47Z
Modified
2026-10-21T02:54:44Z
Severity
  • 6.1 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N CVSS Calculator
Summary
fast-uri vulnerable to URI scheme spoofing via percent-encoded scheme decoding
Details

fast-uri is a dependency-free RFC 3986 URI parser and serializer for Node.js. In versions before 2.4.8, from 3.0.0 through 3.1.8, and from 4.0.0 through 4.2.2, fast-uri percent-decodes the scheme component with the legacy global unescape() function before validating it, so an input whose decoded scheme is a dangerous token is emitted as a live scheme even though RFC 3986 does not allow percent-encoding in a scheme and no other parser accepts it. An application that screens dangerous schemes on the raw input and then stores or renders the normalized or resolved result can turn an inert string into an executable javascript, data, or vbscript URL, producing a stored or reflected cross-site scripting vector, and the equal() comparison treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists. The issue is fixed in fast-uri 2.4.8, 3.1.9, and 4.2.3, and users should upgrade to one of these versions or later. As a workaround, reject input whose scheme part contains a percent sign, or check the parsed scheme against an allowlist after normalization and use that same parsed result rather than the raw string.

Database specific
{
    "cna_assigner":  "openjs",
    "cwe_ids":  [
        "CWE-172",
        "CWE-180"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/110xxx/CVE-2026-110306.json",
    "unresolved_ranges":  [
        {
            "extracted_events":  [
                {
                    "range":  [
                        {
                            "fixed":  "2.4.8"
                        },
                        {
                            "introduced":  "3.0.0"
                        },
                        {
                            "fixed":  "3.1.9"
                        },
                        {
                            "introduced":  "4.0.0"
                        },
                        {
                            "fixed":  "4.2.3"
                        }
                    ],
                    "source":  "AFFECTED_FIELD",
                    "strategy":  "StandardRange"
                }
            ]
        },
        {
            "extracted_events":  [
                {
                    "range":  [
                        {
                            "fixed":  "2.4.8"
                        }
                    ],
                    "source":  "DESCRIPTION"
                }
            ]
        }
    ]
}
References

Affected packages

Git / github.com/fastify/fast-uri

Affected ranges

Type
GIT
Repo
https://github.com/fastify/fast-uri
Events
Database specific
Show details
{
    "extracted_events":  [
        {
            "range":  [
                {
                    "introduced":  "3.0.0"
                },
                {
                    "last_affected":  "3.1.8"
                }
            ],
            "source":  "DESCRIPTION"
        },
        {
            "range":  [
                {
                    "introduced":  "4.0.0"
                },
                {
                    "last_affected":  "4.2.2"
                }
            ],
            "source":  "DESCRIPTION"
        }
    ]
}

Affected versions

v3.*
v3.0.0
v3.0.1
v3.0.2
v3.0.3
v3.0.4
v3.0.5
v3.0.6
v3.1.0
v3.1.1
v3.1.2
v3.1.3
v3.1.4
v3.1.5
v3.1.6
v3.1.7
v3.1.8
v4.*
v4.0.0
v4.0.1
v4.1.0
v4.1.1
v4.1.2
v4.1.3
v4.1.4
v4.1.5
v4.2.0
v4.2.1
v4.2.2

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-110306.json"