Description
serverless-dns is a RethinkDNS resolver that deploys to Cloudflare Workers, Deno Deploy, Fastly, and Fly.io. Versions through abd including 0.1.30 have a vulnerability where the pr.yml GitHub Action interpolates in an unsafe manner untrusted input, specifically the github.event.pull_request.head.repo.clone_url and github.head_ref, to a command in the runner. Due to the action using the pull_request_target trigger it has permissive permissions by default. An unauthorized attacker can exploit this vulnerability to push arbitrary data to the repository. The subsequent impact on the end-user is executing the attackers' code when running serverless-dns. This is fixed in commit c5537dd, and expected to be released in 0.1.31.
References (2)
Core 2
Core References
Patch x_refsource_misc
https://github.com/serverless-dns/serverless-dns/commit/c5537dd7f203c59f2b86d1e295c2371f3533946a
Vendor Advisory x_refsource_confirm
https://github.com/serverless-dns/serverless-dns/security/advisories/GHSA-9g7x-737f-5xpc
Scores
CVSS v4
9.3
EPSS
0.0033
EPSS Percentile
25.1%
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
total
Details
CWE
CWE-77
Status
published
Published
Sep 30, 2025
Tracked Since
Feb 18, 2026