---
cve: "CVE-2026-58050"
severity: "HIGH"
cvss: 8.3
epss: "71%"
vendor: "libssh2"
kev: false
exploited: false
published: "2026-06-28 02:16:32"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-04T01:54:49+02:00"
---

# CVE-2026-58050

> 8.3 HIGH · 🧪 PoC

## Beschreibung

libssh2 through 1.11.1 reads an attacker-controlled 32-bit attribute count from a publickey-subsystem response and uses it in the allocation num_attrs * sizeof(libssh2_publickey_attribute) without bounds checking, so on 32-bit platforms the multiplication overflows to an undersized buffer. A malicious SSH server can then drive the attribute-parsing loop to write past the allocation, causing a heap buffer overflow in a connecting libssh2 client.

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Hoch | good |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Referenzen

- <https://github.com/bikini/exploitarium/tree/main/libssh2-publickey-list-calc-poc>
- <https://github.com/libssh2/libssh2/blob/master/src/publickey.c>
- <https://www.vulncheck.com/advisories/libssh2-integer-overflow-in-publickey-subsystem-attribute-allocation>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-58050) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_