CVE-2026-53791
Last modified
CVE-2026-53791 is a critical-severity vulnerability rated 9.1/10 on the CVSS scale. 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.. EPSS estimates a 0.47% chance of exploitation in the next 30 days.
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.
Metrics
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Samba | Rsync | < 3.5.0 |
References
- https://github.com/RsyncProject/rsync/releases/tag/v3.5.0Product, Release Notes
- https://www.vulncheck.com/advisories/rsync-daemon-ip-spoofing-via-proxy-protocol-headerRelease Notes, Third Party Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-53791?
How severe is CVE-2026-53791?
How do I fix CVE-2026-53791?
How Strix Helps
- Same Subject, Wrong User: A Cross-Issuer Account Takeover in n8nStrix found an identity-binding bug in n8n's token-exchange flow enabling account takeover.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-53786rsync before 3.5.0 contains a filter rule bypass vulnerabili…6.5
- CVE-2026-53787Amasty Order Attributes for Magento 2 before version 4.0.0 c…9.8
- CVE-2026-53788rsync before 3.5.0 contains a newline injection vulnerabilit…6.5
- CVE-2026-53789rsync before 3.5.0 contains an improper path handling vulner…8.1
- CVE-2026-5379An issue that allowed MCP agents to access certificate infor…3
- CVE-2026-53790rsync before 3.5.0 contains multiple command and argument in…8.1
- CVE-2026-53792rsync before 3.5.0 contains an out-of-bounds read vulnerabil…6.5
- CVE-2026-53793rsync before 3.5.0 contains a path confinement bypass vulner…7.4
- CVE-2026-53794rsync before 3.5.0 contains a logic error in --max-alloc han…5.3
- CVE-2026-53795rsync before 3.5.0 contains an arbitrary file write vulnerab…8.1
- CVE-2026-53796rsync before 3.5.0 contains a time-of-check to time-of-use (…6.3
- CVE-2026-53797rsync before 3.5.0 contains a symlink race condition vulnera…4.7
Are you affected by CVE-2026-53791?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST