How severe is CVE-2026-25833?

CVE-2026-25833 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 none, integrity none, and availability high.

Is CVE-2026-25833 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-25833?

CVE-2026-25833 primarily affects Trustedfirmware Mbed Tls. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-25833?

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-2026-25833 have an EU (EUVD) identifier?

Yes. CVE-2026-25833 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17997.

When was CVE-2026-25833 published?

CVE-2026-25833 was published on 2026-04-01 and last updated on 2026-06-17.

CVE-2026-25833

CVE-2026-25833 is a high-severity vulnerability in Trustedfirmware Mbed Tls 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-121.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (23rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-17997
Weakness: CWE-121
Affected product: Trustedfirmware Mbed Tls
Published: 2026-04-01
Last modified: 2026-06-17

Description

Mbed TLS 3.5.0 to 3.6.5 fixed in 3.6.6 and 4.1.0 has a buffer overflow in the x509_inet_pton_ipv6() function

Frequently asked questions

What is CVE-2026-25833?: Mbed TLS 3.5.0 to 3.6.5 fixed in 3.6.6 and 4.1.0 has a buffer overflow in the x509_inet_pton_ipv6() function
How severe is CVE-2026-25833?: CVE-2026-25833 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 none, integrity none, and availability high.
Is CVE-2026-25833 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-25833?: CVE-2026-25833 primarily affects Trustedfirmware Mbed Tls. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-25833?: 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-2026-25833 have an EU (EUVD) identifier?: Yes. CVE-2026-25833 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17997.
When was CVE-2026-25833 published?: CVE-2026-25833 was published on 2026-04-01 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:trustedfirmware:mbed_tls:*:*:*:*:*:*:*:*
cpe:2.3:a:trustedfirmware:mbed_tls:4.0.0:*:*:*:*:*:*:*

More vulnerabilities in Trustedfirmware Mbed Tls

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