Cisco Snort3 DCE/RPC OOB Read Leak via DCE/RPC Buff Overflow
CVE-2026-20027 Published on January 7, 2026

Cisco Snort DCERPC Stub Data Out of Bounds Read
Multiple Cisco products are affected by a vulnerability in the processing of DCE/RPC requests that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to leak sensitive information or to restart, resulting in an interruption of packet inspection. This vulnerability is due to an error in buffer handling logic when processing DCE/RPC requests, which can result in a buffer out-of-bounds read. An attacker could exploit this vulnerability by sending a large number of DCE/RPC requests through an established connection that is inspected by Snort 3. A successful exploit could allow the attacker to obtain sensitive information in the Snort 3 data stream.

NVD

Vulnerability Analysis

CVE-2026-20027 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a small impact on confidentiality, a small impact on integrity and availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
NONE
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
LOW
Integrity Impact:
NONE
Availability Impact:
NONE

Weakness Type

What is an Information Disclosure Vulnerability?

The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

CVE-2026-20027 has been classified to as an Information Disclosure vulnerability or weakness.


Affected Versions

Cisco Secure Firewall Threat Defense (FTD) Software: Cisco UTD SNORT IPS Engine Software:

Exploit Probability

EPSS
0.04%
Percentile
12.73%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.