NASA CryptoLib up to 1.3.3 CCSDS Space Data Link Security Protocol Crypto_TC_ApplySecurity integer underflow

Summaryinfo

A vulnerability was found in NASA CryptoLib up to 1.3.3. It has been classified as very critical. This affects the function Crypto_TC_ApplySecurity of the component CCSDS Space Data Link Security Protocol Handler. Performing a manipulation results in integer underflow. This vulnerability is reported as CVE-2025-30356. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in NASA CryptoLib up to 1.3.3. It has been classified as very critical. This affects the function Crypto_TC_ApplySecurity of the component CCSDS Space Data Link Security Protocol Handler. The manipulation with an unknown input leads to a integer underflow vulnerability. CWE is classifying the issue as CWE-191. The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2025-30356 since 03/21/2025. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/02/2025).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• NASA

Name

• CryptoLib

Version

• 1.3.0
• 1.3.1
• 1.3.2
• 1.3.3

Website

• Product: https://github.com/nasa/CryptoLib/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion