{"id":"UBUNTU-CVE-2026-55588","details":"ORAS (OCI Registry As Storage) is a CLI and library for managing artifacts in OCI registries. In ORAS CLI versions up to and including 1.3.2, the recursive referrer traversal does not track visited descriptors, so a malicious OCI registry that returns a cyclic referrer graph causes unbounded recursion and memory growth. This affects oras discover, whose recursive traversal is enabled by default because the --depth option defaults to 0 (unlimited), as well as the recursive referrer counting used by the oras backup and oras restore workflows. A cyclic graph can be as simple as A referring to B and B referring back to A. A malicious registry can use this to cause a client-side denial of service, exhausting CPU and memory and hanging automation or CI/CD pipelines that run ORAS against untrusted registry metadata. The vulnerability does not extend to code execution, artifact substitution, or integrity bypass. This issue has been fixed in version 1.3.3.","modified":"2026-09-02T19:35:54.080751116Z","published":"2026-08-25T21:17:00Z","upstream":["CVE-2026-55588"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-55588"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-55588"},{"type":"REPORT","url":"https://github.com/oras-project/oras/security/advisories/GHSA-298f-872v-2rcx"}],"affected":[{"package":{"name":"oras","ecosystem":"Ubuntu:Pro:26.04:LTS","purl":"pkg:deb/ubuntu/oras?arch=source&distro=esm-apps%2Fresolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.2.0-1","1.3.0-1","1.3.0-1ubuntu0.26.04.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"oras","binary_version":"1.3.0-1ubuntu0.26.04.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-55588.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}