# CVE-2009-0591: Security feature bypass in n/a

> Remote attackers can repudiate invalid CMS signatures due to improper error handling in OpenSSL, bypassing signature validation when CMS is enabled.

- **Severity:** Low 2.6 (`AV:N/AC:H/Au:N/C:N/I:P/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 27 Mar 2009
- **Updated:** 7 Aug 2024
- **Also known as:** GHSA-xfgm-r927-x577

## What is CVE-2009-0591?

CVE-2009-0591 is a low-severity vulnerability in Openssl Openssl, published on 27 Mar 2009. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The CMS_verify function in OpenSSL 0.9.8h through 0.9.8j, when CMS is enabled, does not properly handle errors associated with malformed signed attributes, which allows remote attackers to repudiate a signature that originally appeared to be valid but was actually invalid.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2009-0591?

It affects 1 product.


Products: Openssl Openssl.

## How do I fix CVE-2009-0591?

Upgrade to a fixed version.

## Is CVE-2009-0591 being exploited?

There is no known exploitation of CVE-2009-0591 in the wild and no public exploit code.

## Other vulnerabilities in Openssl Openssl

- [CVE-2009-3245](https://insights.sbomify.com/CVE-2009-3245/): Null dereference in n/a (critical 10.0)
- [CVE-2006-3738](https://insights.sbomify.com/CVE-2006-3738/): Memory corruption in n/a (critical 10.0)
- [CVE-2026-63073](https://insights.sbomify.com/CVE-2026-63073/): Untrusted Sender DN Used as Format String in CMP Response Validation (critical 9.8)
- [CVE-2016-6309](https://insights.sbomify.com/CVE-2016-6309/): Use after free in n/a (critical 9.8)
- [CVE-2016-0799](https://insights.sbomify.com/CVE-2016-0799/): Integer overflow in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2009-0591 and fix it if it is affected.

What it is: CVE-2009-0591 is a low-severity vulnerability in Openssl Openssl, published on 27 Mar 2009. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2009-0591 in the wild and no public exploit code.

Affected product: Openssl Openssl. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2009-0591/ (Markdown: https://insights.sbomify.com/CVE-2009-0591/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2009-0591
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2009-0591
- OSV: https://osv.dev/vulnerability/CVE-2009-0591

---
From sbomify Insights: https://insights.sbomify.com/CVE-2009-0591/
Summaries are generated and may contain mistakes; the official description above is the record.