Heap Buffer Overflow in 389 Directory Server by Red Hat
CVE-2026-18355
7.5HIGH
What is CVE-2026-18355?
A heap buffer overflow vulnerability exists within the SASL I/O layer of the 389 Directory Server. This flaw is exploited when the wrapped-record length read from the network is improperly validated, allowing an attacker to manipulate buffer lengths. Affected systems can face severe consequences, including denial of service and the risk of remote code execution. The issue arises specifically when an attacker successfully binds to the server with integrity protection enabled, facilitating malicious data input that could overflow a defined heap buffer. This condition enables unauthorized access and manipulation of memory, highlighting the importance of timely updates and patches.
References
CVSS V3.1
Score:
7.5
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged
Timeline
Vulnerability published
Vulnerability Reserved
Credit
Red Hat would like to thank Adam Korczynski (Ada Logics), Arthur Chan (Ada Logics), David Korczynski (Ada Logics), and Team (Anthropic) for reporting this issue.