Cyber Resilience

CVE-2026-53784

Samba Rsync ≤ 3.5.0

Public PoC
Published
13 August 2026
Modified
31 August 2026
Patch / advisory
CVSS Score v4 8.4
Click a component to see what it means
Raw vectorCVSS:4.0/AV:L/AC:L/AT:N/PR:L/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
EPSS Score 0.0024 15th percentile
Risk Priority 32 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-53784 is a high-severity Link Following (CWE-59) vulnerability in Samba Rsync. Its CVSS base score is 8.4 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Path Interception (T1034); ranked at the 15th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-6 (Least Privilege) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

rsync before 3.5.0 contains a path traversal vulnerability that allows remote clients to access files outside the intended module root when use chroot is disabled and the module root path or a component of it is a symlink. The daemon…

more

calls chdir() to the module root at session initialization without resolving symlinks via realpath() or equivalent, causing subsequent relative-path operations to reference files relative to the symlink target rather than the intended module root, enabling unauthorized file access.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1034 Path Interception Persistence
**This technique has been deprecated.
T1547.009 Shortcut Modification Persistence
Adversaries may create or modify shortcuts that can execute a program during system boot or user login.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-53795Same product: Samba Rsync
CVE-2026-53803Same product: Samba Rsync
CVE-2026-43619Same product: Samba Rsync
CVE-2026-53801Same product: Samba Rsync
CVE-2026-53799Same product: Samba Rsync
CVE-2026-53802Same product: Samba Rsync
CVE-2026-29518Same product: Samba Rsync
CVE-2026-45232Same product: Samba Rsync
CVE-2026-53789Same product: Samba Rsync
CVE-2026-43617Same product: Samba Rsync

Affected Assets

samba
rsync
≤ 3.5.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V15.4.2

Mitigating Controls (NIST 800-53 r5) AI

Proper enforcement of access authorizations on the resolved target resource stops a link from reaching an unintended object.

Least-privilege limits the damage an attacker can cause after following an unintended link.

Validating file-name inputs can reject or canonicalize names that resolve to links before access occurs.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 partial match
prevents

Secure SDLC practices directly require code to validate paths and avoid unsafe link following.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Secure SDLC practices can mandate link-resolution checks and canonicalization before file access.

prevents

Application security requirements can explicitly require safe handling of symbolic links and path traversal.

prevents

Secure architecture principles include input validation and safe file-access design patterns.

prevents

Secure coding standards directly address canonicalization and symlink attacks during implementation.

finds

Security testing can detect link-following flaws before release.

mitigates

Access-control rules can limit which files are reachable, reducing exposure to malicious links.

References