# CVE-2023-33958: Default `maxSignatureAttempts` in `notation verify` enables an endless data attack in notation

> An attacker with registry access can cause denial of service by adding excessive signatures, triggering resource exhaustion during verification.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L`)
- **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:** Yes
- **Published:** 6 Jun 2023
- **Updated:** 2 Aug 2024
- **Also known as:** GHSA-rvrx-rrwh-r9p6, GO-2023-1831

## What is CVE-2023-33958?

CVE-2023-33958 is a medium-severity denial of service vulnerability in notaryproject notation, published on 6 Jun 2023. 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

notation is a CLI tool to sign and verify OCI artifacts and container images. An attacker who has compromised a registry and added a high number of signatures to an artifact can cause denial of service of services on the machine, if a user runs notation verify command on the same machine. The problem has been fixed in the release v1.0.0-rc.6. Users should upgrade their notation packages to v1.0.0-rc.6 or above. Users unable to upgrade may restrict container registries to a set of secure and trusted container registries.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2023-33958?

3 open source packages ship an affected version, including github.com/notaryproject/notation. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/notaryproject/notation` | Go | All versions | 1.0.0-rc.6 |
| `github.com/notaryproject/notation` | Go | All versions | 1.0.0-rc.6 |
| `github.com/notaryproject/notation` | Go | All versions | 1.0.0-rc.6 |

Products: Notaryproject Notation-Go.

## How do I fix CVE-2023-33958?

Upgrade github.com/notaryproject/notation to 1.0.0-rc.6 or later.

## Is CVE-2023-33958 being exploited?

There is no known exploitation of CVE-2023-33958 in the wild and no public exploit code.

## Other vulnerabilities in notaryproject notation

- [CVE-2023-33959](https://insights.sbomify.com/CVE-2023-33959/): Verification bypass can cause users into verifying the wrong artifact (high 8.4)
- [CVE-2023-25656](https://insights.sbomify.com/CVE-2023-25656/): notation-go has excessive memory allocation on verification (high 7.5)
- [CVE-2024-23332](https://insights.sbomify.com/CVE-2024-23332/): Client configured with permissive trust policies susceptible to rollback attack in Notary Project (medium 4.0)
- [CVE-2024-51491](https://insights.sbomify.com/CVE-2024-51491/): Process crash during CRL-based revocation check on OS using separate mount point for temp Directory in notation-go (low 3.3)
- [CVE-2023-33957](https://insights.sbomify.com/CVE-2023-33957/): Denial of service from high number of artifact signatures in notation (low 2.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-33958 and fix it if it is affected.

What it is: CVE-2023-33958 is a medium-severity denial of service vulnerability in notaryproject notation, published on 6 Jun 2023. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2023-33958 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/notaryproject/notation (Go): affected all versions; fixed in 1.0.0-rc.6
- github.com/notaryproject/notation (Go): affected all versions; fixed in 1.0.0-rc.6
- github.com/notaryproject/notation (Go): affected all versions; fixed in 1.0.0-rc.6

Task:
1. 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.
2. 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.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2023-33958/ (Markdown: https://insights.sbomify.com/CVE-2023-33958/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-33958
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-33958
- OSV: https://osv.dev/vulnerability/CVE-2023-33958

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-33958/
Summaries are generated and may contain mistakes; the official description above is the record.