curl SMB UAF: freed memory used on repeated request
CVE-2026-3805 Published on March 11, 2026

use after free in SMB connection reuse
When doing a second SMB request to the same host again, curl would wrongly use a data pointer pointing into already freed memory.

NVD

Vulnerability Analysis

CVE-2026-3805 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. An automatable proof of concept (POC) exploit exists. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.

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

Weakness Type

What is a Dangling pointer Vulnerability?

Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code.

CVE-2026-3805 has been classified to as a Dangling pointer vulnerability or weakness.


Products Associated with CVE-2026-3805

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Haxx Curl
 
Canonical Ubuntu Linux
 

Affected Versions

curl:

Exploit Probability

EPSS
0.04%
Percentile
11.84%

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.