libsodium Elliptic Curve crypto_core_ed25519_is_valid_point incomplete blacklist

Summaryinfo

A vulnerability has been found in libsodium and classified as critical. This impacts the function crypto_core_ed25519_is_valid_point of the component Elliptic Curve Handler. This manipulation causes incomplete blacklist. The identification of this vulnerability is CVE-2025-69277. The attack can only be executed locally. There is no exploit available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability classified as critical was found in libsodium (the affected version unknown). Affected by this vulnerability is the function crypto_core_ed25519_is_valid_point of the component Elliptic Curve Handler. The manipulation with an unknown input leads to a incomplete blacklist vulnerability. The CWE definition for the vulnerability is CWE-184. The product implements a protection mechanism that relies on a list of inputs (or properties of inputs) that are not allowed by policy or otherwise require other action to neutralize before additional processing takes place, but the list is incomplete, leading to resultant weaknesses. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

libsodium before ad3004e, in atypical use cases involving certain custom cryptography or untrusted data to crypto_core_ed25519_is_valid_point, mishandles checks for whether an elliptic curve point is valid because it sometimes allows points that aren't in the main cryptographic group.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2025-69277 since 12/31/2025. The exploitation appears to be difficult. Attacking locally is a requirement. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1562.006 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 281493 (Linux Distros Unpatched Vulnerability : CVE-2025-69277), which helps to determine the existence of the flaw in a target environment.

Applying the patch ad3004ec8731730e93fcfbbc824e67eadc1c1bae is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the vulnerability database at Tenable (281493). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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Name

• libsodium

License

• open-source

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

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Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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