# CVE-2020-7760: Regular Expression Denial of Service (ReDoS)

> An attacker can cause a denial of service in CodeMirror via a specially crafted input triggering a regular expression denial of service.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 30 Oct 2020
- **Updated:** 17 Sep 2024
- **Also known as:** DEBIAN-CVE-2020-7760, DSA-4789-1, GHSA-4gw3-8f77-f72c, UBUNTU-CVE-2020-7760

## What is CVE-2020-7760?

CVE-2020-7760 is a medium-severity denial of service vulnerability in Oracle Essbase, published on 30 Oct 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

This affects the package codemirror before 5.58.2; the package org.apache.marmotta.webjars:codemirror before 5.58.2. The vulnerable regular expression is located in https://github.com/codemirror/CodeMirror/blob/cdb228ac736369c685865b122b736cd0d397836c/mode/javascript/javascript.jsL129. The ReDOS vulnerability of the regex is mainly due to the sub-pattern (s|/*.*?*/)*

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2020-7760?

2 open source packages ship an affected version, including codemirror. It affects 6 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `codemirror` | npm | All versions | 5.58.2 |
| `codemirror` | npm | All versions | 5.58.2 |

Products: Codemirror Codemirror, Oracle Application Express, Oracle Enterprise Manager Express User Interface, Oracle Essbase, Oracle Hyperion Data Relationship Management, Oracle Spatial Studio.

## How do I fix CVE-2020-7760?

Upgrade codemirror to 5.58.2 or later.

## Is CVE-2020-7760 being exploited?

There is no known exploitation of CVE-2020-7760 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-7760 and fix it if it is affected.

What it is: CVE-2020-7760 is a medium-severity denial of service vulnerability in Oracle Essbase, published on 30 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-2020-7760 in the wild and no public exploit code.

Affected packages and fixed versions:
- codemirror (npm): affected all versions; fixed in 5.58.2
- codemirror (npm): affected all versions; fixed in 5.58.2

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-2020-7760/ (Markdown: https://insights.sbomify.com/CVE-2020-7760/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-7760
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-7760
- OSV: https://osv.dev/vulnerability/CVE-2020-7760

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-7760/
Summaries are generated and may contain mistakes; the official description above is the record.