{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-18738 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2026-18738 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-18738 is a medium-severity code injection vulnerability in shlinkio Shlink, published on 3 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-18738 and fix it if it is affected.\n\nWhat it is: CVE-2026-18738 is a medium-severity code injection vulnerability in shlinkio Shlink, published on 3 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.\nExploitation: There is no known exploitation of CVE-2026-18738 in the wild and no public exploit code.\n\nAffected product: shlinkio Shlink. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-18738/ (Markdown: https://insights.sbomify.com/CVE-2026-18738/index.md)","id":"CVE-2026-18738","markdown":"https://insights.sbomify.com/CVE-2026-18738/index.md","name":"CVE-2026-18738","record":{"aliases":["GHSA-ghrv-q878-w45x"],"analysis":{"component_type":"web_application","fix_type":"upgrade","impacts":["code_execution"],"network_reachable":"yes","non_default_config":false,"product_category":"URL shortener","requires_auth":"none","summary":"Unauthenticated attackers can inject malicious formulas into CSV exports, leading to code execution on administrators' machines when files are opened.","user_interaction":"required","vuln_class":"code_injection"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"VulnCheck","cpe":[],"cvss":{"score":5.1,"severity":"medium","source":"cna","vector":"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","version":"4.0"},"cwes":[{"id":"CWE-1236","name":"Improper Neutralization of Formula Elements in a CSV File"}],"description":"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.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":false,"headline":"Shlink CSV Formula Injection via Visit Export CLI","id":"CVE-2026-18738","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"code_injection","year":"2026"},"n_packages":0,"n_references":3,"next":{"headline":"Popt-devel: popt-static: off-by-one in poptstuffargs","id":"CVE-2026-18739"},"packages":[],"prev":{"headline":"Shlink Blind SQL Injection via tags/stats orderBy Parameter","id":"CVE-2026-18737"},"products":["Shlink"],"published":"2026-08-03","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-08-04","vendors":["shlinkio"]},"summary":"Unauthenticated attackers can inject malicious formulas into CSV exports, leading to code execution on administrators' machines when files are opened.","url":"https://insights.sbomify.com/CVE-2026-18738/"}