cURL doublefree via GSASL context cleanup bug
CVE-2026-8925 Published on July 3, 2026

SASL double-free
The curl logic that works with SASL authentication could end up cleaning up the GSASL context *twice* without clearing the pointer in between, making it `free()` the same pointer twice.

NVD

Vulnerability Analysis

CVE-2026-8925 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 be critical as this vulnerability has a high impact to the confidentiality, integrity and availability of this component.

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

Weakness Type

What is a Double-free Vulnerability?

The product calls free() twice on the same memory address, potentially leading to modification of unexpected memory locations. When a program calls free() twice with the same argument, the program's memory management data structures become corrupted. This corruption can cause the program to crash or, in some circumstances, cause two later calls to malloc() to return the same pointer. If malloc() returns the same value twice and the program later gives the attacker control over the data that is written into this doubly-allocated memory, the program becomes vulnerable to a buffer overflow attack.

CVE-2026-8925 has been classified to as a Double-free vulnerability or weakness.


Products Associated with CVE-2026-8925

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Canonical Ubuntu Linux
 
Haxx Curl
 

Affected Versions

curl: curl: curl: