CVE-2026-18738 (GCVE-0-2026-18738)

Vulnerability from cvelistv5 – Published: 2026-08-03 20:53 – Updated: 2026-08-04 15:05
VLAI
Title
Shlink CSV Formula Injection via Visit Export CLI
Summary
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.
Severity
5.1 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
4.7 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-04 14:28 UTC
CWE
  • CWE-1236 - Improper Neutralization of Formula Elements in a CSV File
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7783 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
shlinkio Shlink Affected: 5.0.0 , ≤ 5.1.5 (git)
guessed Create a notification for this product.
Date Public
2026-08-03 00:00
Credits
Theodosis Paidakis
Show details on NVD website
To clipboard 

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