CVE-2026-55588 ORAS CLI: Cyclic Referrer Graph Can Cause Unbounded Recursion and Resource Consumption
A malicious OCI registry can cause unbounded recursion and resource exhaustion in ORAS CLI, leading to client-side denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-55588?
CVE-2026-55588 is a medium-severity denial of service vulnerability in oras-project oras, published on 25 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.
Official description
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.
Which versions are affected by CVE-2026-55588?
3 open source packages ship an affected version, including oras.land/oras.
| Package | Affected | Fixed in |
|---|---|---|
oras.land/oras Go | All versions | 1.3.3 |
oras.land/oras Go | All versions | 1.3.3 |
oras.land/oras Go | All versions | 1.3.3 |
How do I fix CVE-2026-55588?
Upgrade oras.land/oras to 1.3.3 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-55588 being exploited?
There is no known exploitation of CVE-2026-55588 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-55588, GHSA-298f-872v-2rcx, GO-2026-6317, UBUNTU-CVE-2026-55588.