# CVE-2025-45770: Weak cryptography in n/a

> The JWT library may use weak encryption if the application does not configure sufficient key lengths, potentially exposing sensitive data.

- **Severity:** High 7.0 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/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:** 31 Jul 2025
- **Updated:** 17 Aug 2025
- **Also known as:** DEBIAN-CVE-2025-45770, GHSA-hp45-3w87-63c3, MINI-4vmq-c2wg-3j3h, UBUNTU-CVE-2025-45770

## What is CVE-2025-45770?

CVE-2025-45770 is a high-severity vulnerability in n/a, published on 31 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

jwt v5.4.3 was discovered to contain weak encryption. NOTE: this issue has been disputed on the basis that key lengths are expected to be set by an application, not by this library. This dispute is subject to review under CNA rules 4.1.4, 4.1.14, and other rules; the dispute tagging is not meant to recommend an outcome for this CVE Record.

Weakness: CWE-326 (Inadequate Encryption Strength)

## Which versions are affected by CVE-2025-45770?

It affects 1 product.


Products: Jwt Project Jwt.

## How do I fix CVE-2025-45770?

No fix has been published for CVE-2025-45770 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-45770 being exploited?

There is no known exploitation of CVE-2025-45770 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-45770 and fix it if it is affected.

What it is: CVE-2025-45770 is a high-severity vulnerability in n/a, published on 31 Jul 2025. 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-2025-45770 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-2025-45770/ (Markdown: https://insights.sbomify.com/CVE-2025-45770/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-45770
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-45770
- OSV: https://osv.dev/vulnerability/CVE-2025-45770

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-45770/
Summaries are generated and may contain mistakes; the official description above is the record.