CVE-2023-27537
A double free vulnerability exists in libcurl <8.0.0 when sharing HSTS data between separate "handles".
Published Mar 30, 2023 · updated Oct 14, 2026 · haxx libcurl
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.
Code
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No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Mar 30, 2023 · NIST NVD
Detected
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.
Oct 14, 2026 · NIST NVD
Updated
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.
Affected
- cpe broadcom/brocade fabric operating system firmwareversion unspecified
- cpe haxx/libcurl7.88.0
- cpe haxx/libcurl7.88.1
- cpe netapp/active iq unified managerversion unspecified
- cpe netapp/clustered data ontap9.0
- cpe netapp/h300s firmwareversion unspecified
- cpe netapp/h410s firmwareversion unspecified
- cpe netapp/h500s firmwareversion unspecified
- cpe netapp/h700s firmwareversion unspecified
- cpe splunk/universal forwarderversion unspecified
Sources
- CVE.orgVulnerability recordCVE-2023-27537
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2023-27537
30-day exploitation probability 1.9%
first.org - NIST NVDVulnerability recordCVE-2023-27537
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 mut
nvd.nist.gov