Vulnerability · Published Apr 1, 2026 · Assigned by mitre
CVE-2026-25833
High 7.5
In plain English
A high-severity stack buffer overflow in the mbedtls package (Alpine). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.3%top 74.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | mbedtls | 3.6.6-r0 | ALPINE-CVE-2026-25833 |
| Alpine:v3.21 | mbedtls | 3.6.6-r0 | ALPINE-CVE-2026-25833 |
| Alpine:v3.22 | mbedtls | 3.6.6-r0 | ALPINE-CVE-2026-25833 |
| Alpine:v3.23 | mbedtls | 3.6.6-r0 | ALPINE-CVE-2026-25833 |
| Alpine:v3.24 | mbedtls | 3.6.6-r0 | ALPINE-CVE-2026-25833 |
| Alpine:v3.24 | mbedtls3 | 3.6.6-r0 | ALPINE-CVE-2026-25833 |
| Debian:12 | mbedtls | no fix listed | DEBIAN-CVE-2026-25833 |
| Debian:13 | mbedtls | no fix listed | DEBIAN-CVE-2026-25833 |
| Debian:14 | mbedtls | 3.6.6-0.1 | DEBIAN-CVE-2026-25833 |
| Ubuntu:25.10 | mbedtls | no fix listed | UBUNTU-CVE-2026-25833 |
| Ubuntu:26.04:LTS | mbedtls | no fix listed | UBUNTU-CVE-2026-25833 |
| Ubuntu:26.10 | mbedtls | no fix listed | UBUNTU-CVE-2026-25833 |
Affected products (as reported)
Weakness: CWE-121 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H