CVE-2026-70454
Description
A flaw was found in rsync. This vulnerability allows on-path attackers to intercept encrypted sessions by presenting self-signed or otherwise invalid certificates. The flaw exists because rsync fails to validate server Transport Layer Security (TLS) certificates against a trusted Certificate Authority (CA) or verify certificate hostname matching. This enables attackers to decrypt or tamper with rsync session content without being detected by the client.
Statement
This is an Important flaw in rsync that allows on-path attackers to intercept encrypted sessions. The vulnerability arises from rsync's failure to properly validate server TLS certificates against a trusted Certificate Authority or verify hostname matching. This enables attackers to decrypt or tamper with rsync session content, posing a significant risk to data confidentiality and integrity for Red Hat users utilizing rsync with TLS in compromised network environments.
Mitigation
To mitigate this issue, avoid using rsync in `openssl mode` or `stunnel mode` for encrypted sessions. Instead, utilize rsync over SSH, which provides robust authentication and encryption mechanisms. For example: `rsync -avz -e ssh /source user@remote:/destination`. This requires SSH to be configured and accessible on both the client and server.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 8.7 | N/A | 8 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | High | N/A | High |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | Required |
| Scope | Changed | N/A | Changed |
| Confidentiality | High | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
cve.org: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N
Understanding the Weakness (CWE)
Integrity,Authentication
Technical Impact: Bypass Protection Mechanism; Gain Privileges or Assume Identity
When a certificate is invalid or malicious, it might allow an attacker to spoof a trusted entity by interfering in the communication path between the host and client. The product might connect to a malicious host while believing it is a trusted host, or the product might be deceived into accepting spoofed data that appears to originate from a trusted host.
Frequently Asked Questions
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