---
cve: "CVE-2026-77756"
severity: "LOW"
cvss: 3.7
epss: ""
vendor: "Apache Software Foundation"
kev: false
exploited: false
published: "2026-09-23 12:17:06"
tags: [cve, security, low]
source: tsecurity.de CVE-Dossier
exported: "2026-10-01T03:06:41+02:00"
---

# CVE-2026-77756

> 3.7 LOW

## Beschreibung

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in Apache Tomcat caused by processing the transfer-encoding header for an HTTP/1.0 request may allow an attacker to cause one request from another user to fail when Tomcat is located behind a reverse proxy.



This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.47 through 9.0.121.



The following versions were EOL at the time the CVE was created but are 
known to be affected: from 8.5.67 through 8.5.100. Other unsupported versions may also be affected.



Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **no**
  - Technical Impact: **partial**

## CVSS-Vektor

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

| 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 | Keine | good |
| I Integrität | Keine | good |
| A Verfügbarkeit | Gering | warn |

## BSI-Hinweise (deutsch)

- [Apache Tomcat: Mehrere Schwachstellen](https://wid.cert-bund.de/portal/wid/sicherheitshinweis/WID-SEC-W-2026-3527) — _BSI-Einstufung: mittel_
  Ein Angreifer kann mehrere Schwachstellen in Apache Tomcat ausnutzen, um Sicherheitsvorkehrungen zu umgehen, um einen Denial of Service Angriff durchzuführen und um Daten zu manipulieren.

## Referenzen

- <https://lists.apache.org/thread/bl5b6rxqh3vb2k9bj2794vhor7o6xl3z>
- <http://www.openwall.com/lists/oss-security/2026/09/23/22>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-77756) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_