CVE-2026-86344
HIGH
MEDIUM
Priority: 0.03
BB Relevance:
75/100
Published: 2026-10-01
Modified: 2026-11-05
First seen: 2026-11-05
Status: active
Attack Surface
Network
Low Complexity
No Auth
No Interaction
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
None
UI:
None
S:
Unchanged
C:
None
I:
None
A:
High
Description
A flaw was found in 389-ds-base. An unauthenticated remote attacker can send a complete LDAP operation followed by the first bytes of an incomplete LDAPMessage on the same connection, causing the server to hand that connection to a second worker thread before the first worker's result is flushed. The second worker blocks until nsslapd-ioblocktimeout while holding the connection mutex, preventing delivery of the completed operation's result. Repeating this across a small number of connections proportional to the configured worker-thread pool size exhausts the entire pool under default configuration, denying service to all clients (anonymous and authenticated, plaintext and TLS) for as long as the attacker maintains the connections.
Weakness Classification (1)
References & Advisories (2)
vdb-entry
x_refsource_REDHAT
issue-tracking
x_refsource_REDHAT