---
cve: "CVE-2026-4873"
severity: "MEDIUM"
cvss: 5.9
epss: "33%"
vendor: "curl"
kev: false
exploited: false
published: "2026-05-13 13:01:55"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-12T05:31:38+02:00"
---

# CVE-2026-4873

> 5.9 MEDIUM

## Beschreibung

A vulnerability exists where a connection requiring TLS incorrectly reuses an
existing unencrypted connection from the same connection pool. If an initial
transfer is made in clear-text (via IMAP, SMTP, or POP3), a subsequent request
to that same host bypasses the TLS requirement and instead transmit data
unencrypted.

## CVSS-Vektor

```
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Hoch | good |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Keine | good |
| A Verfügbarkeit | Keine | good |

## Patch verfügbar (OSV)

- a05f34973e6c4bb629d018f7cb51487be1c904d8 (Commit)

## Referenzen

- <https://curl.se/docs/CVE-2026-4873.json>
- <https://curl.se/docs/CVE-2026-4873.html>
- <https://hackerone.com/reports/3621851>
- <http://www.openwall.com/lists/oss-security/2026/04/29/7>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-4873) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_