CVE-2026-23967
HIGHCVE-2026-23967 is a high-severity (CVSS 7.5) CWE-347 vulnerability in juneandgreen sm-crypto. O3 Security detects and blocks CVE-2026-23967 exploitation at runtime via eBPF exploit-chain detection and L7 egress monitoring, even on unpatched systems.
sm-crypto provides JavaScript implementations of the Chinese cryptographic algorithms SM2, SM3, and SM4. A signature malleability vulnerability exists in the SM2 signature verification…
Description
sm-crypto provides JavaScript implementations of the Chinese cryptographic algorithms SM2, SM3, and SM4. A signature malleability vulnerability exists in the SM2 signature verification logic of the sm-crypto library prior to version 0.3.14. An attacker can derive a new valid signature for a previously signed message from an existing signature. Version 0.3.14 patches the issue.
Affected Products
sm-cryptojuneandgreenDetection & mitigation playbook
Vendor / applianceDetect
Inventory every juneandgreen sm-crypto deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.
Fix
Apply the juneandgreen sm-crypto security patch or hotfix for CVE-2026-23967 on the affected version, following the vendor advisory for your exact build.
Workarounds
Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.
How O3 protects you
O3 detects and blocks CVE-2026-23967 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.
Tailored to CVE-2026-23967. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-23967 being exploited in your environment?
O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2026-23967 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.