# CVE-2025-20244: Denial of service in Cisco Adaptive Security Appliance (ASA) Software

> Authenticated remote attackers can cause Cisco ASA and FTD devices to reload via crafted HTTP requests to the SSL VPN service.

- **Severity:** High 7.7 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Aug 2025
- **Updated:** 14 Aug 2025
- **Also known as:** GHSA-jj2c-3m89-73r8

## What is CVE-2025-20244?

CVE-2025-20244 is a high-severity denial of service vulnerability in Cisco Adaptive Security Appliance (ASA) Software, published on 14 Aug 2025. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability in the Remote Access SSL VPN service for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow a remote attacker that is authenticated as a VPN user to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition.

This vulnerability is due to incomplete error checking when parsing an HTTP header field value. An attacker could exploit this vulnerability by sending a crafted HTTP request to a targeted Remote Access SSL VPN service on an affected device. A successful exploit could allow the attacker to cause a DoS condition, which would cause the affected device to reload.

Weakness: CWE-1287 (Improper Validation of Specified Type of Input)

## Which versions are affected by CVE-2025-20244?


## How do I fix CVE-2025-20244?

No fix has been published for CVE-2025-20244 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-20244 being exploited?

There is no known exploitation of CVE-2025-20244 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-20244 and fix it if it is affected.

What it is: CVE-2025-20244 is a high-severity denial of service vulnerability in Cisco Adaptive Security Appliance (ASA) Software, published on 14 Aug 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-20244 in the wild and no public exploit code.

Affected product: Cisco Adaptive Security Appliance (ASA) Software. 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-2025-20244/ (Markdown: https://insights.sbomify.com/CVE-2025-20244/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-20244
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-20244
- OSV: https://osv.dev/vulnerability/CVE-2025-20244

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-20244/
Summaries are generated and may contain mistakes; the official description above is the record.