High severity · published Sep 6, 2026
CVE-2026-80231
native CA store conn reuse
7.5
CVSS
0.9%
EPSS
No
On KEV
Description
A flaw in libcurl makes it wrongly reuse an existing HTTPS connection setup
for a given hostname even when using a different Native CA Store setting
(`CURLSSLOPT_NATIVE_CA`) than when the connection was created.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 59% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CU
curl · curl
7.71.0 before 8.14.2; 8.15.0 before 8.16.1; 8.17.0 before 8.20.1; 8.21.0 before 8.22.0; 148534db57dda611cf8516e92e4d6e35fc1e5074 before 7be1e70cb6bcd83e130ecfe8cb91b6a7dcdeff42; 8.21.0; +34 more · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-80231
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-80231
Mitigation
https://curl.se/docs/CVE-2026-80231.html
Vendor Advisory
https://curl.se/docs/CVE-2026-80231.json
Exploit
https://hackerone.com/reports/3969368
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