# CVE-2020-27978: Denial of service in n/a

> Remote unauthenticated attackers can cause denial of service via Java heap exhaustion in Shibboleth Identity Provider login flows.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 28 Oct 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-x3qc-wj2q-xv5h

## What is CVE-2020-27978?

CVE-2020-27978 is a high-severity denial of service vulnerability in n/a, published on 28 Oct 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Shibboleth Identify Provider 3.x before 3.4.6 has a denial of service flaw. A remote unauthenticated attacker can cause a login flow to trigger Java heap exhaustion due to the creation of objects in the Java Servlet container session.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2020-27978?

It affects 1 product.


Products: Shibboleth Identity Provider.

## How do I fix CVE-2020-27978?

No fix has been published for CVE-2020-27978 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-27978 being exploited?

There is no known exploitation of CVE-2020-27978 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2014-3603](https://insights.sbomify.com/CVE-2014-3603/): Improper Validation of Certificate with Host Mismatch in Shibboleth Identity Provider and OpenSAML Java (medium 5.9)
- [CVE-2015-1796](https://insights.sbomify.com/CVE-2015-1796/): Improper Certificate Validation in Shibboleth Identity Provider and OpenSAML (medium 4.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-27978 and fix it if it is affected.

What it is: CVE-2020-27978 is a high-severity denial of service vulnerability in n/a, published on 28 Oct 2020. 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-2020-27978 in the wild and no public exploit code.

Affected product: n/a. 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-2020-27978/ (Markdown: https://insights.sbomify.com/CVE-2020-27978/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-27978
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-27978
- OSV: https://osv.dev/vulnerability/CVE-2020-27978

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-27978/
Summaries are generated and may contain mistakes; the official description above is the record.