How severe is CVE-2026-7531?

CVE-2026-7531 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-7531 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-7531?

CVE-2026-7531 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-7531?

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

Does CVE-2026-7531 have an EU (EUVD) identifier?

Yes. CVE-2026-7531 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39554.

When was CVE-2026-7531 published?

CVE-2026-7531 was published on 2026-06-25 and last updated on 2026-06-26.

CVE-2026-7531

CVE-2026-7531 is a critical-severity vulnerability in Wolfssl with a CVSS 3.x base score of 9.8. 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-416.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v4: 2.3
EPSS exploit prediction: 0% (27th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-39554
Weakness: CWE-416
Affected product: Wolfssl
Published: 2026-06-25
Last modified: 2026-06-26

Description

Use-after-free in PQC hybrid key-share handling. This is an incomplete-fix follow-up to CVE-2026-5460 (released in 5.9.1): a malicious TLS 1.3 server sending a truncated PQC hybrid KeyShare can still trigger the error cleanup path to operate on freed memory.

Frequently asked questions

What is CVE-2026-7531?: Use-after-free in PQC hybrid key-share handling. This is an incomplete-fix follow-up to CVE-2026-5460 (released in 5.9.1): a malicious TLS 1.3 server sending a truncated PQC hybrid KeyShare can still trigger the error cleanup path to operate on freed memory.
How severe is CVE-2026-7531?: CVE-2026-7531 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-7531 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-7531?: CVE-2026-7531 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-7531?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-7531 have an EU (EUVD) identifier?: Yes. CVE-2026-7531 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39554.
When was CVE-2026-7531 published?: CVE-2026-7531 was published on 2026-06-25 and last updated on 2026-06-26.

References

Affected products (1)

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

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Other CWE-416 (Use After Free) vulnerabilities

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CVE-2026-4725 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 149…
CVE-2026-4688 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox…
CVE-2025-24085 — Critical (CVSS 10.0): A use after free issue was addressed with improved memory management. This issue is fixed in iOS 18.3 and iPadOS 18.3,…
CVE-2024-43102 — Critical (CVSS 10.0): Concurrent removals of certain anonymous shared memory mappings by using the UMTX_SHM_DESTROY sub-request of…
CVE-2021-32495 — Critical (CVSS 10.0): Radare2 has a use-after-free vulnerability in pyc parser's get_none_object function. Attacker can read freed memory…

Browse all CWE-416 (Use After Free) vulnerabilities →