Vulnerabilities

Vulnerability · 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

Published Apr 1, 2026 · catalog updated Jun 17, 2026 · mbed tls

Check if you run it

No confirmed exploitation is on record for CVE-2026-25833. EPSS is 0.53%. Act only if a listed version of mbed tls is installed.

Gaps on this record

  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
High7.5
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.53%
Remediation
Advisory link
Affected products
cpe trustedfirmware/mbed tls

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

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • cpe trustedfirmware/mbed tls4.0.0

How to fix CVE-2026-25833

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-25833. EPSS is 0.53%. Act only if a listed version of mbed tls is installed.

Which versions are affected?

Compare what you have installed with trustedfirmware/mbed tls 4.0.0. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-121: Stack-based Buffer Overflow. EPSS 0.53%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Apr 1, 2026 · NIST NVD

    Detected

    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

  2. Jun 17, 2026 · NIST NVD

    Updated

    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

Sources

  • CVE.orgVulnerability recordCVE-2026-25833

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-25833

    30-day exploitation probability 0.5%

    first.org
  • NIST NVDVulnerability recordCVE-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

    nvd.nist.gov

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.