How severe is CVE-2026-25834?

CVE-2026-25834 has a CVSS 3.x base score of 6.5, rated medium 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 low.

Is CVE-2026-25834 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-25834?

CVE-2026-25834 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-2026-25834?

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

Does CVE-2026-25834 have an EU (EUVD) identifier?

Yes. CVE-2026-25834 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17967.

When was CVE-2026-25834 published?

CVE-2026-25834 was published on 2026-04-01 and last updated on 2026-06-17.

CVE-2026-25834

CVE-2026-25834 is a medium-severity vulnerability in Trustedfirmware Mbed Tls with a CVSS 3.x base score of 6.5. 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-295.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-17967
Weakness: CWE-295
Affected product: Trustedfirmware Mbed Tls
Published: 2026-04-01
Last modified: 2026-06-17

Description

Mbed TLS v3.3.0 up to 3.6.5 and 4.0.0 allows Algorithm Downgrade.

Frequently asked questions

What is CVE-2026-25834?: Mbed TLS v3.3.0 up to 3.6.5 and 4.0.0 allows Algorithm Downgrade.
How severe is CVE-2026-25834?: CVE-2026-25834 has a CVSS 3.x base score of 6.5, rated medium 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 low.
Is CVE-2026-25834 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-25834?: CVE-2026-25834 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-2026-25834?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-25834 have an EU (EUVD) identifier?: Yes. CVE-2026-25834 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17967.
When was CVE-2026-25834 published?: CVE-2026-25834 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…
CVE-2024-49195 — Critical (CVSS 9.8): Mbed TLS 3.5.x through 3.6.x before 3.6.2 has a buffer underrun in pkwrite when writing an opaque key pair
CVE-2024-45159 — Critical (CVSS 9.8): An issue was discovered in Mbed TLS 3.x before 3.6.1. With TLS 1.3, when a server enables optional authentication of…
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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