How severe is CVE-2025-12888?

CVE-2025-12888 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2025-12888 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-12888?

CVE-2025-12888 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-12888?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2025-12888 have an EU (EUVD) identifier?

Yes. CVE-2025-12888 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-198523.

When was CVE-2025-12888 published?

CVE-2025-12888 was published on 2025-11-21 and last updated on 2026-06-17.

CVE-2025-12888

CVE-2025-12888 is a high-severity vulnerability in Wolfssl with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-203.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 1.0
EPSS exploit prediction: 0% (18th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-198523
Weakness: CWE-203
Affected product: Wolfssl
Published: 2025-11-21
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2025-12888?: 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.
How severe is CVE-2025-12888?: CVE-2025-12888 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2025-12888 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-12888?: CVE-2025-12888 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-12888?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-12888 have an EU (EUVD) identifier?: Yes. CVE-2025-12888 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-198523.
When was CVE-2025-12888 published?: CVE-2025-12888 was published on 2025-11-21 and last updated on 2026-06-17.

References

https://https://github.com/wolfSSL/wolfssl/pull/9275

Affected products (1)

cpe:2.3:a:wolfssl:wolfssl:5.8.2:*:*:*:*:*:*:*

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