How severe is CVE-2025-11931?

CVE-2025-11931 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.

Is CVE-2025-11931 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-11931?

CVE-2025-11931 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-11931?

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-2025-11931 have an EU (EUVD) identifier?

Yes. CVE-2025-11931 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-198522.

When was CVE-2025-11931 published?

CVE-2025-11931 was published on 2025-11-21 and last updated on 2026-06-17.

CVE-2025-11931

CVE-2025-11931 is a high-severity vulnerability in Wolfssl with a CVSS 3.x base score of 8.2. 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-191.

Key facts

Severity: High (CVSS 3.x base score 8.2)
CVSS v4: 2.1
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-198522
Weakness: CWE-191
Affected product: Wolfssl
Published: 2025-11-21
Last modified: 2026-06-17

Description

Integer Underflow Leads to Out-of-Bounds Access in XChaCha20-Poly1305 Decrypt. This issue is hit specifically with a call to the function wc_XChaCha20Poly1305_Decrypt() which is not used with TLS connections, only from direct calls from an application.

Frequently asked questions

What is CVE-2025-11931?: Integer Underflow Leads to Out-of-Bounds Access in XChaCha20-Poly1305 Decrypt. This issue is hit specifically with a call to the function wc_XChaCha20Poly1305_Decrypt() which is not used with TLS connections, only from direct calls from an application.
How severe is CVE-2025-11931?: CVE-2025-11931 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.
Is CVE-2025-11931 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-11931?: CVE-2025-11931 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-11931?: 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-2025-11931 have an EU (EUVD) identifier?: Yes. CVE-2025-11931 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-198522.
When was CVE-2025-11931 published?: CVE-2025-11931 was published on 2025-11-21 and last updated on 2026-06-17.

References

https://github.com/wolfSSL/wolfssl/pull/9223

Affected products (1)

cpe:2.3:a:wolfssl:wolfssl:5.8.4:*:*:*:*:*:*:*

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