CVE-2026-18738

Shlink versions 5.0.0 through 5.1.5 contain a CSV formula injection vulnerability that allows unauthenticated remote attackers to plant spreadsheet formulas into exported visit data by supplying malicious values in User-Agent, Referer, or request path headers beginning with formula-triggering characters such as =, +, -, or @. Attackers can craft a single unauthenticated request against any short URL to embed DDE or WEBSERVICE formula payloads into CSV cells, which are then executed on an administrator's client machine when the exported CSV file is opened in a spreadsheet application that evaluates formulas.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/shlinkio/shlink
https://github.com/theopaid/CSV-formula-injection-in-visit-exports-shlink-
https://www.vulncheck.com/advisories/shlink-csv-formula-injection-via-visit-export-cli

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-03 21:16

Updated : 2026-09-09 20:35

NVD link : CVE-2026-18738

Mitre link : CVE-2026-18738

CVE.ORG link : CVE-2026-18738

JSON object : View

Products Affected

No product.

CWE

CWE-1236

Improper Neutralization of Formula Elements in a CSV File

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