CVE-2026-53791
rsync < 3.5.0 Daemon IP Spoofing via PROXY Protocol Header
Description
rsync daemon before 3.5.0 contains an IP address spoofing vulnerability that allows unauthenticated remote attackers to bypass IP-based access controls by sending a crafted PROXY protocol header with a forged source address. Attackers who can connect directly to the rsync daemon can inject a spoofed source IP in the PROXY protocol header to circumvent hosts allow/deny rules, gaining unauthorized access that would otherwise be blocked based on their real source address.
INFO
Published Date :
Aug. 13, 2026, 3:19 p.m.
Last Modified :
Aug. 31, 2026, 3:38 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | CRITICAL | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | CRITICAL | [email protected] | ||||
| CVSS 3.1 | CRITICAL | MITRE-CVE | ||||
| CVSS 4.0 | CRITICAL | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | CRITICAL | [email protected] |
Solution
- Update rsync daemon to version 3.5.0 or later.
- Configure access controls to mitigate spoofing risks.
- Review and restrict network access to the rsync daemon.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-53791.
| URL | Resource |
|---|---|
| https://github.com/RsyncProject/rsync/releases/tag/v3.5.0 | Product Release Notes |
| https://github.com/RsyncProject/rsync/security/advisories/GHSA-h2q9-5fr8-w635 | Vendor Advisory |
| https://www.vulncheck.com/advisories/rsync-daemon-ip-spoofing-via-proxy-protocol-header | Release Notes Third Party Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-53791 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-53791
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-53791 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-53791 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Aug. 31, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:* versions up to (excluding) 3.5.0 Added Reference Type VulnCheck: https://github.com/RsyncProject/rsync/releases/tag/v3.5.0 Types: Product, Release Notes Added Reference Type VulnCheck: https://github.com/RsyncProject/rsync/security/advisories/GHSA-h2q9-5fr8-w635 Types: Vendor Advisory Added Reference Type VulnCheck: https://www.vulncheck.com/advisories/rsync-daemon-ip-spoofing-via-proxy-protocol-header Types: Release Notes, Third Party Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Aug. 14, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-53791', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-08-14T18:02:57.002288Z'} -
New CVE Received by [email protected]
Aug. 13, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/RsyncProject/rsync', 'vendor': 'RsyncProject', 'product': 'rsync', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'semver', 'lessThanOrEqual': '3.4.4'}, {'status': 'unaffected', 'version': '3.5.0', 'versionType': 'semver'}], 'packageURL': 'pkg:github/RsyncProject/rsync', 'defaultStatus': 'unaffected'}] Added Description rsync daemon before 3.5.0 contains an IP address spoofing vulnerability that allows unauthenticated remote attackers to bypass IP-based access controls by sending a crafted PROXY protocol header with a forged source address. Attackers who can connect directly to the rsync daemon can inject a spoofed source IP in the PROXY protocol header to circumvent hosts allow/deny rules, gaining unauthorized access that would otherwise be blocked based on their real source address. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N Added CWE CWE-290 Added Reference https://github.com/RsyncProject/rsync/releases/tag/v3.5.0 Added Reference https://github.com/RsyncProject/rsync/security/advisories/GHSA-h2q9-5fr8-w635 Added Reference https://www.vulncheck.com/advisories/rsync-daemon-ip-spoofing-via-proxy-protocol-header