CVE-2023-27537 Use after free in https://github.com/curl/curl

What is CVE-2023-27537?

CVE-2023-27537 is a medium-severity use after free vulnerability in Haxx Libcurl, published on 30 Mar 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A double free vulnerability exists in libcurl <8.0.0 when sharing HSTS data between separate "handles". This sharing was introduced without considerations for do this sharing across separate threads but there was no indication of this fact in the documentation. Due to missing mutexes or thread locks, two threads sharing the same HSTS data could end up doing a double-free or use-after-free.

Weakness: CWE-415

Which versions are affected by CVE-2023-27537?

It affects 9 products.

Products include Broadcom Brocade Fabric Operating System Firmware, Haxx Libcurl, Netapp Active Iq Unified Manager, Netapp Clustered Data Ontap, Netapp H300s Firmware, Netapp H410s Firmware and 3 more.

How do I fix CVE-2023-27537?

Upgrade to a fixed version.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2023-27537 being exploited?

There is no known exploitation of CVE-2023-27537 in the wild and no public exploit code.

Other vulnerabilities in Haxx Libcurl

• CVE-2023-27534 Path traversal in https://github.com/curl/curl High 8.8
• CVE-2021-4197 Privilege escalation in kernel High 7.8
• CVE-2023-27538 Auth bypass in https://github.com/curl/curl High 7.7
• CVE-2021-27218 Integer overflow in n/a High 7.5
• CVE-2021-27219 Integer overflow in n/a High 7.5

All Haxx Libcurl vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as ALPINE-CVE-2023-27537, AZL-25852, AZL-25858, AZL-34603, AZL-38114, CLEANSTART-2026-NT49097 and 4 more.