CVE-2025-12888
- Published: 2025-11-21T23:15:44.970
Vulnerability in X25519 constant-time cryptographic implementations due to timing side channels introduced by compiler optimizations and CPU architecture limitations, specifically with the Xtensa-based ESP32 chips. If targeting Xtensa it is recommended to use the low memory implementations of X25519, which is now turned on as the default for Xtensa.
Related CVE by CWE
No related CWE found.
Top CVE for Vendor
No vendor taxonomy on this entry.
Recently Exploited Similar Vulnerabilities
No recent KEV-listed items for this vendor/product.
How to fix CVE-2025-12888
CVE-2025-12888 is a unknown severity vulnerability affecting the affected product.
Description: Vulnerability in X25519 constant-time cryptographic implementations due to timing side channels introduced by compiler optimizations and CPU architecture limitations, specifically with the Xtensa-based ESP32 chips. If targeting Xtensa it is recommended to use the low memory implementations of X25519, which is now turned on as the default for Xtensa. Related CVE by CWENo related CWE […]
Exploit Difficulty: HARD
⏱️ Time to exploit: > 4 hours
🛠️ Required skills: Advanced security expertise
💰 Public exploits: Rare or not public
How to Fix:
- Check if you're running the affected product
- Update to the latest patched version
- If patching is not immediately possible: restrict network exposure, apply least-privilege access
- Test the fix in a staging environment first
- Review logs for signs of exploitation
- Monitor for IOCs (Indicators of Compromise)
- Enable automatic security updates
- Set up vulnerability monitoring
- Review and harden security configurations
Description: Vulnerability in X25519 constant-time cryptographic implementations due to timing side channels introduced by compiler optimizations and CPU architecture limitations, specifically with the Xtensa-based ESP32 chips. If targeting Xtensa it is recommended to use the low memory implementations of X25519, which is now turned on as the default for Xtensa. Related CVE by CWENo related CWE […]
Exploit Difficulty: HARD
⏱️ Time to exploit: > 4 hours
🛠️ Required skills: Advanced security expertise
💰 Public exploits: Rare or not public
How to Fix:
1 Identify affected systems
- Check if you're running the affected product
2 Immediate actions
- Update to the latest patched version
- If patching is not immediately possible: restrict network exposure, apply least-privilege access
3 Verification
- Test the fix in a staging environment first
- Review logs for signs of exploitation
- Monitor for IOCs (Indicators of Compromise)
4 Long-term prevention
- Enable automatic security updates
- Set up vulnerability monitoring
- Review and harden security configurations
Exploit Difficulty Assessment
HARD
Time to Exploit: > 4 hours
Skills Required: Advanced security expertise
Public Exploits: Rare or not public
Vulnerability Timeline
Nov 21, 2025
Vulnerability Published
CVE details first published to NVD database
Nov 21, 2025
Imported to Database
Added to this CVE tracking system
Detection Rules & IOCs
No specific detection rules generated for this vulnerability type.
No vendor/product data available.