Is This vulnerability exploited in the wild?

No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

How severe is This vulnerability?

Medium severity, with a CVSS score of 4, published 12 February 2025.

Which products and versions are affected?

elliptic (npm) SEMVER:introduced=0,fixed=6.6.1.

Is there a fix for This vulnerability?

Yes. elliptic (npm): upgrade to 6.6.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is This vulnerability attacked?

It is attacked over the network, in a software library.

Check whether you run elliptic (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Elliptic ECDSA private key extraction via malformed input

Severity: medium · CVSS 4 · Published 2025-02-12

Elliptic is a widely-used cryptographic library that implements ECDSA digital signing. A flaw in how it processes malformed input (such as strings) during signature generation causes the same cryptographic nonce to be reused for different messages. This nonce reuse allows an attacker to extract the complete private key after seeing just two signatures, potentially compromising all security operations that depend on that key.

Technologies: elliptic (npm). Vendors: npm.

Quick answers

Is This vulnerability exploited in the wild?: No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
How severe is This vulnerability?: Medium severity, with a CVSS score of 4, published 12 February 2025.
Which products and versions are affected?: elliptic (npm) SEMVER:introduced=0,fixed=6.6.1.
Is there a fix for This vulnerability?: Yes. elliptic (npm): upgrade to 6.6.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is This vulnerability attacked?: It is attacked over the network, in a software library.
Am I affected?: Check whether you run elliptic (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

elliptic (npm): upgrade to 6.6.1 or later
```
npm install elliptic@6.6.1
```

Technical details

The vulnerability is a cryptographic key reuse bug in the ECDSA signing implementation. When processing the message input before signing, the library converts it to a BigNumber (BN) instance; however, the nonce derivation converts a BN to a byte array without accounting for potential representation differences. Different BN values can serialize to identical byte arrays, causing identical nonces to be generated for different messages. An attacker can construct a malformed message (e.g., a hex string or number) that, when signed, produces a nonce collision with a previously-obtained signature. With two signatures sharing the same nonce but different messages, the attacker can solve simultaneous equations to extract the private key. Attack requires the ability to influence a message being signed, but exploitation succeeds after only one such malicious message is processed. The vulnerability affects all versions up to and including 6.6.0; version 6.6.1 contains the fix.

Affected products

indutny elliptic <=6.6.0

Timeline

2025-02-12: disclosed
2025-02-12: patched: version 6.6.1

References

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