# CVE-2025-30356: Heap Buffer Overflow via Incomplete Length Check in `Crypto_TC_ApplySecurity`

> An attacker can trigger a heap buffer overflow in CryptoLib by crafting malicious frames, potentially leading to code execution or denial of service.

- **Severity:** Critical 9.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 1 Apr 2025
- **Updated:** 2 Apr 2025
- **Also known as:** GHSA-6w2x-w7w3-85w2

## What is CVE-2025-30356?

CVE-2025-30356 is a critical memory corruption vulnerability in nasa CryptoLib, published on 1 Apr 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

CryptoLib provides a software-only solution using the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP) to secure communications between a spacecraft running the core Flight System (cFS) and a ground station. In 1.3.3 and earlier, a heap buffer overflow vulnerability persists in the Crypto_TC_ApplySecurity function due to an incomplete validation check on the fl (frame length) field. Although CVE-2025-29912 addressed an underflow issue involving fl, the patch fails to fully prevent unsafe calculations. As a result, an attacker can still craft malicious frames that cause a negative tf_payload_len, which is then interpreted as a large unsigned value, leading to a heap buffer overflow in a memcpy call.

Weakness: CWE-787 (Out-of-bounds Write), CWE-191 (Integer Underflow (Wrap or Wraparound))

## Which versions are affected by CVE-2025-30356?

It affects 1 product.


Products: Nasa Cryptolib.

## How do I fix CVE-2025-30356?

No fix has been published for CVE-2025-30356 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-30356 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-30356 exists.

## Other vulnerabilities in nasa CryptoLib

- [CVE-2025-30216](https://insights.sbomify.com/CVE-2025-30216/): CryptoLib Has Heap Overflow in Crypto_TM_ProcessSecurity due to Unchecked Secondary Header Length (critical 9.4)
- [CVE-2025-29909](https://insights.sbomify.com/CVE-2025-29909/): CryptoLib's Crypto_TC_ApplySecurity() Has a Heap Buffer Overflow Vulnerability (high 8.9)
- [CVE-2025-29911](https://insights.sbomify.com/CVE-2025-29911/): CryptoLib Has Heap Buffer Overflow in Crypto_AOS_ProcessSecurity Function (high 8.9)
- [CVE-2025-29912](https://insights.sbomify.com/CVE-2025-29912/): CryptoLib Has Heap Buffer Overflow Due to Unsigned Integer Underflow in Crypto_TC_ProcessSecurity (high 8.9)
- [CVE-2025-29913](https://insights.sbomify.com/CVE-2025-29913/): CryptoLib's Crypto_TC_Prep_AAD Has Buffer Overflow Due to Integer Underflow (high 8.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-30356 and fix it if it is affected.

What it is: CVE-2025-30356 is a critical memory corruption vulnerability in nasa CryptoLib, published on 1 Apr 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-30356 exists.

Affected product: nasa CryptoLib. 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-2025-30356/ (Markdown: https://insights.sbomify.com/CVE-2025-30356/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-30356
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-30356
- OSV: https://osv.dev/vulnerability/CVE-2025-30356

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From sbomify Insights: https://insights.sbomify.com/CVE-2025-30356/
Summaries are generated and may contain mistakes; the official description above is the record.