How severe is CVE-2026-34874?

CVE-2026-34874 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-2026-34874 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34874?

CVE-2026-34874 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-2026-34874?

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-2026-34874 have an EU (EUVD) identifier?

Yes. CVE-2026-34874 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-18003.

When was CVE-2026-34874 published?

CVE-2026-34874 was published on 2026-04-01 and last updated on 2026-06-17.

CVE-2026-34874

CVE-2026-34874 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-476.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (20th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-18003
Weakness: CWE-476
Affected product: Trustedfirmware Mbed Tls
Published: 2026-04-01
Last modified: 2026-06-17

Description

An issue was discovered in Mbed TLS through 3.6.5 and 4.x through 4.0.0. There is a NULL pointer dereference in distinguished name parsing that allows an attacker to write to address 0.

Frequently asked questions

What is CVE-2026-34874?: An issue was discovered in Mbed TLS through 3.6.5 and 4.x through 4.0.0. There is a NULL pointer dereference in distinguished name parsing that allows an attacker to write to address 0.
How severe is CVE-2026-34874?: CVE-2026-34874 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-2026-34874 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34874?: CVE-2026-34874 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-2026-34874?: 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-2026-34874 have an EU (EUVD) identifier?: Yes. CVE-2026-34874 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-18003.
When was CVE-2026-34874 published?: CVE-2026-34874 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

CVE-2026-34877 — Critical (CVSS 9.8): An issue was discovered in Mbed TLS versions from 2.19.0 up to 3.6.5, Mbed TLS 4.0.0. Insufficient protection of…
CVE-2026-34875 — Critical (CVSS 9.8): An issue was discovered in Mbed TLS through 3.6.5 and TF-PSA-Crypto 1.0.0. A buffer overflow can occur in public key…
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CVE-2024-45158 — Critical (CVSS 9.8): An issue was discovered in Mbed TLS 3.6 before 3.6.1. A stack buffer overflow in mbedtls_ecdsa_der_to_raw() and…
CVE-2023-45199 — Critical (CVSS 9.8): Mbed TLS 3.2.x through 3.4.x before 3.5 has a Buffer Overflow that can lead to remote Code execution.

All CVEs affecting Trustedfirmware Mbed Tls →

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Browse all CWE-476 (NULL Pointer Dereference) vulnerabilities →