How Sigstore quickly patched an upstream vulnerability
Summary On October 3, 2022, Dex, the federated identity provider that Sigstore uses to issue identity tokens, published CVE-2022-39222 with a GitHub Security Advisory. Sigstore was vulnerable to this CVE, but we were able to quickly mitigate the vulnerability in June before an official fix was published. Details On June 13, 2022, Joern Schneeweisz from the GitLab Security Research Team disclosed a vulnerability to Sigstore where an attacker executing a phishing campaign against a user can acquire a user’s identity token through a backchannel.