knownhost callback mismatches key as missing
Summary
| CVE | CVE-2026-87865 |
|---|---|
| State | PUBLISHED |
| Assigner | curl |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-20 21:17:20 UTC |
| Updated | 2026-10-30 12:16:46 UTC |
| 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. |
Risk And Classification
Primary CVSS: v3.1 7.4 HIGH from ADP
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS: 0.002440000 probability, percentile 0.156210000 (date 2026-10-30)
Problem Types: CWE-295 | CWE-295 Improper Certificate Validation | CWE-295 CWE-295 Improper Certificate Validation
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | DECLARED | 7.4 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 7.4 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
HighPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
NoneCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Curl | Curl | affected 8.22.0 8.22.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.21.0 8.21.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.20.0 8.20.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.19.0 8.19.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.18.0 8.18.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.17.0 8.17.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.16.0 8.16.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.15.0 8.15.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.14.1 8.14.1 semver | Not specified |
| CNA | Curl | Curl | affected 8.14.0 8.14.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.13.0 8.13.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.12.1 8.12.1 semver | Not specified |
| CNA | Curl | Curl | affected 8.12.0 8.12.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.11.1 8.11.1 semver | Not specified |
| CNA | Curl | Curl | affected 8.11.0 8.11.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.10.1 8.10.1 semver | Not specified |
| CNA | Curl | Curl | affected 8.10.0 8.10.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.9.1 8.9.1 semver | Not specified |
| CNA | Curl | Curl | affected 8.9.0 8.9.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.8.0 8.8.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.7.1 8.7.1 semver | Not specified |
| CNA | Curl | Curl | affected 8.7.0 8.7.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.6.0 8.6.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.5.0 8.5.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.4.0 8.4.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.3.0 8.3.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.2.1 8.2.1 semver | Not specified |
| CNA | Curl | Curl | affected 8.2.0 8.2.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.1.2 8.1.2 semver | Not specified |
| CNA | Curl | Curl | affected 8.1.1 8.1.1 semver | Not specified |
| CNA | Curl | Curl | affected 8.1.0 8.1.0 semver | Not specified |
| CNA | Curl | Curl | affected 8.0.1 8.0.1 semver | Not specified |
| CNA | Curl | Curl | affected 8.0.0 8.0.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.88.1 7.88.1 semver | Not specified |
| CNA | Curl | Curl | affected 7.88.0 7.88.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.87.0 7.87.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.86.0 7.86.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.85.0 7.85.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.84.0 7.84.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.83.1 7.83.1 semver | Not specified |
| CNA | Curl | Curl | affected 7.83.0 7.83.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.82.0 7.82.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.81.0 7.81.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.80.0 7.80.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.79.1 7.79.1 semver | Not specified |
| CNA | Curl | Curl | affected 7.79.0 7.79.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.78.0 7.78.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.77.0 7.77.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.76.1 7.76.1 semver | Not specified |
| CNA | Curl | Curl | affected 7.76.0 7.76.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.75.0 7.75.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.74.0 7.74.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.73.0 7.73.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.72.0 7.72.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.71.1 7.71.1 semver | Not specified |
| CNA | Curl | Curl | affected 7.71.0 7.71.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.70.0 7.70.0 semver | Not specified |
| CNA | Curl | Curl | affected 7.69.1 7.69.1 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| curl.se/docs/CVE-2026-87865.html | 2499f714-1537-4658-8207-48ae4bb9eae9 | curl.se | |
| hackerone.com/reports/3975408 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | hackerone.com | |
| curl.se/docs/CVE-2026-87865.json | 2499f714-1537-4658-8207-48ae4bb9eae9 | curl.se | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Bobbeh Rhino (en)
CNA: Bobbeh Rhino (en)
There are currently no legacy QID mappings associated with this CVE.