# CVE-2025-48965: Null dereference in mbedtls

> A NULL pointer dereference in Mbed TLS allows attackers to cause a denial of service via crafted ASN.1 data.

- **Severity:** Medium 4.0 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 20 Jul 2025
- **Updated:** 3 Nov 2025
- **Also known as:** ALPINE-CVE-2025-48965, DEBIAN-CVE-2025-48965, GHSA-qxjv-288g-w43x, JLSEC-2025-230, ROOT-OS-DEBIAN-12-CVE-2025-48965, UBUNTU-CVE-2025-48965

## What is CVE-2025-48965?

CVE-2025-48965 is a medium-severity vulnerability in Arm Mbed Tls, published on 20 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Mbed TLS before 3.6.4 has a NULL pointer dereference because mbedtls_asn1_store_named_data can trigger conflicting data with val.p of NULL but val.len greater than zero.

Weakness: CWE-476 (NULL Pointer Dereference), CWE-696 (Incorrect Behavior Order)

## Which versions are affected by CVE-2025-48965?

It affects 1 product.


Products: Arm Mbed Tls.

## How do I fix CVE-2025-48965?

Upgrade to a fixed version.

## Is CVE-2025-48965 being exploited?

There is no known exploitation of CVE-2025-48965 in the wild and no public exploit code.

## Other vulnerabilities in Arm Mbed Tls

- [CVE-2026-34877](https://insights.sbomify.com/CVE-2026-34877/): Deserialization in n/a (critical 9.8)
- [CVE-2022-46393](https://insights.sbomify.com/CVE-2022-46393/): Memory corruption in n/a (critical 9.8)
- [CVE-2021-44732](https://insights.sbomify.com/CVE-2021-44732/): Use after free in n/a (critical 9.8)
- [CVE-2017-18187](https://insights.sbomify.com/CVE-2017-18187/): Integer overflow in n/a (critical 9.8)
- [CVE-2018-0487](https://insights.sbomify.com/CVE-2018-0487/): Memory corruption in ARM mbed TLS before 1.3.22, before 2.1.10, and before 2.7.0 (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-48965 and fix it if it is affected.

What it is: CVE-2025-48965 is a medium-severity vulnerability in Arm Mbed Tls, published on 20 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-2025-48965 in the wild and no public exploit code.

Affected product: Arm Mbed Tls. 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-2025-48965/ (Markdown: https://insights.sbomify.com/CVE-2025-48965/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-48965
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-48965
- OSV: https://osv.dev/vulnerability/CVE-2025-48965

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-48965/
Summaries are generated and may contain mistakes; the official description above is the record.