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.
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.
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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Affected Versions
curl:- Version 8.13.0 and below 8.14.2 is affected.
- Version 8.15.0 and below 8.16.1 is affected.
- Version 8.17.0 and below 8.19.0 is affected.
- Version f4831daa9b2a97e8a2921d6b62cc4dfdd0d8646e and below e090be9f73a7a71459ef678c7cc4b1f75e3ea883 is affected.
- Version 8.18.0 is affected.
- Version 8.17.0 is affected.
- Version 8.16.0 is affected.
- Version 8.15.0 is affected.
- Version 8.14.1 is affected.
- Version 8.14.0 is affected.
- Version 8.13.0 is affected.
Exploit Probability
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.