CVE-2026-4258

All versions of the package sjcl are vulnerable to Improper Verification of Cryptographic Signature due to missing point-on-curve validation in sjcl.ecc.basicKey.publicKey(). An attacker can recover a victim's ECDH private key by sending crafted off-curve public keys and observing ECDH outputs. The dhJavaEc() function directly returns the raw x-coordinate of the scalar multiplication result (no hashing), providing a plaintext oracle without requiring any decryption feedback.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://gist.github.com/Kr0emer/2560f98edb10b0b34f2438cd63913c47
https://github.com/bitwiseshiftleft/sjcl/blob/master/core/ecc.js%23L454-L461
https://github.com/bitwiseshiftleft/sjcl/commit/ee307459972442a17beebc29dc331fffd8aff796
https://security.snyk.io/vuln/SNYK-JS-SJCL-15369617
https://gist.github.com/Kr0emer/2560f98edb10b0b34f2438cd63913c47
https://security.snyk.io/vuln/SNYK-JS-SJCL-15369617

Configurations

No configuration.

History

17 Mar 2026, 14:20

Type	Values Removed	Values Added
CWE		CWE-325
References	~~() https://gist.github.com/Kr0emer/2560f98edb10b0b34f2438cd63913c47 -~~	() https://gist.github.com/Kr0emer/2560f98edb10b0b34f2438cd63913c47 -
References	~~() https://security.snyk.io/vuln/SNYK-JS-SJCL-15369617 -~~	() https://security.snyk.io/vuln/SNYK-JS-SJCL-15369617 -

17 Mar 2026, 06:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-17 06:16

Updated : 2026-03-17 14:20

NVD link : CVE-2026-4258

Mitre link : CVE-2026-4258

CVE.ORG link : CVE-2026-4258

JSON object : View

Products Affected

No product.

CWE

CWE-347

Improper Verification of Cryptographic Signature

CWE-325

Missing Cryptographic Step

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