Vulnerability · Published Aug 4, 2026 · Assigned by mitre
CVE-2026-67857
High 7.5
In plain English
A high-severity out-of-bounds read in the open62541 package (Debian). Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 50% of all known vulnerabilities).
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.6%top 49.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
open62541 1.5.5 contains an out-of-bounds read in the client-side function responseReadNamespacesArray() in src/client/ua_client_connect.c.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:13 | open62541 | no fix listed | DEBIAN-CVE-2026-67857 |
| Debian:14 | open62541 | no fix listed | DEBIAN-CVE-2026-67857 |
| Ubuntu:26.04:LTS | open62541 | no fix listed | UBUNTU-CVE-2026-67857 |
| Ubuntu:26.10 | open62541 | no fix listed | UBUNTU-CVE-2026-67857 |
Affected products (as reported)
Weakness: CWE-125 · Vector: CVSS:3.1/AC:L/AV:N/A:H/C:N/I:N/PR:N/S:U/UI:N
References
- https://github.com/open62541/open62541/issues/8104
- https://github.com/open62541/open62541/blob/v1.5.5/src/client/ua_client_connect.c
- https://github.com/open62541/open62541/blob/v1.5.5/examples/client_connect.c
- https://github.com/open62541/open62541/blob/v1.5.5/examples/client_connect_loop.c
- https://github.com/gff-cw/information/issues/9