Unscored severity · published Oct 20, 2026
CVE-2026-87865
knownhost callback mismatches key as missing
–
CVSS
0.2%
EPSS
No
On KEV
Description
When libcurl uses libssh2 with a hashed `known_hosts` file, an unrelated
initial entry can cause host key validation to report a key *mismatch* as a
*missing* key to the `CURLOPT_SSH_KEYFUNCTION` callback.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 15% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CU
curl · curl
8.22.0 through 8.22.0; 8.21.0 through 8.21.0; 8.20.0 through 8.20.0; 8.19.0 through 8.19.0; 8.18.0 through 8.18.0; 8.17.0 through 8.17.0; +34 more · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-87865
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-87865
curl.se
https://curl.se/docs/CVE-2026-87865.html
curl.se
https://curl.se/docs/CVE-2026-87865.json
hackerone.com
https://hackerone.com/reports/3975408
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