How severe is CVE-2026-5507?

CVE-2026-5507 has a CVSS 3.x base score of 4.0, rated medium severity. It is exploitable over local access with high attack complexity, requires high privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-5507 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-5507?

CVE-2026-5507 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-5507?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-5507 have an EU (EUVD) identifier?

Yes. CVE-2026-5507 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-21216.

When was CVE-2026-5507 published?

CVE-2026-5507 was published on 2026-04-09 and last updated on 2026-06-17.

CVE-2026-5507

CVE-2026-5507 is a medium-severity vulnerability in Wolfssl with a CVSS 3.x base score of 4.0. 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-502.

Key facts

Severity: Medium (CVSS 3.x base score 4.0)
CVSS v4: 4.1
EPSS exploit prediction: 0% (7th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-21216
Weakness: CWE-502
Affected product: Wolfssl
Published: 2026-04-09
Last modified: 2026-06-17

Description

When restoring a session from cache, a pointer from the serialized session data is used in a free operation without validation. An attacker who can poison the session cache could trigger an arbitrary free. Exploitation requires the ability to inject a crafted session into the cache and for the application to call specific session restore APIs.

Frequently asked questions

What is CVE-2026-5507?: When restoring a session from cache, a pointer from the serialized session data is used in a free operation without validation. An attacker who can poison the session cache could trigger an arbitrary free. Exploitation requires the ability to inject a crafted session into the cache and for the application to call specific session restore APIs.
How severe is CVE-2026-5507?: CVE-2026-5507 has a CVSS 3.x base score of 4.0, rated medium severity. It is exploitable over local access with high attack complexity, requires high privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-5507 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-5507?: CVE-2026-5507 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-5507?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-5507 have an EU (EUVD) identifier?: Yes. CVE-2026-5507 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-21216.
When was CVE-2026-5507 published?: CVE-2026-5507 was published on 2026-04-09 and last updated on 2026-06-17.

References

https://github.com/wolfSSL/wolfssl/pull/10088

Affected products (1)

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

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