CVE-2026-25833: trustedfirmware mbed_tls Stack-based Buffer Overflow
CVSS: 7.5v3.1HighAnalyzed
AliasesALPINE-CVE-2026-25833UBUNTU-CVE-2026-25833DEBIAN-CVE-2026-25833
Published 01-04-2026Last modified 01-04-2026
Vulnerability summary
CVE-2026-25833 is a high (CVSS 7.5) Stack-based Buffer Overflow vulnerability in trustedfirmware mbed_tls. EPSS estimates a 0.53% chance of exploitation in the next 30 days, higher than 43.5% of scored vulnerabilities.
CVSS score
7.5/10
010
High · v3.1 (CVE.org)EPSS score
0.53%
0%100%
Low · +0.22 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 4 · Related 4Timeline
- 01-04-2026PublishedVulnerability first disclosed.
- 01-04-2026Last modifiedVulnerability information updated.
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
CVSS metrics
5 scores · 5 sources · 1 versionHigh 7.5Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HSourcesAll 5 agree
- OSV · AlpineEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- NVDNIST7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.53%
Chance of exploitation in the next 30 days
Percentile
44%
Versus all other CVEs
30-day change
+0.22 pp
From 0.31% on 20-09-2026
20-09-202620-10-2026
EPSS score0.53%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Alpine1 product
- mbedtls< 3.6.6-r0
Debian1 product
- mbedtlsAll versions (No fix recorded) | < 3.6.6-0.1
Trustedfirmware1 product
- mbed_tls≥ 3.5.0, < 3.6.6 | 4.0.0
Ubuntu1 product
- mbedtlsAll versions (No fix recorded)
4 vendors · 4 products
References
6 links- mbed-tls.readthedocs.io/en/latest/security-advisories/Vendor Advisory
