rsync < 3.5.0 TOCTOU Race Condition Directory Escape via rrsync (CVE-2026-53783) | HOL Guard CVE

High · CVSS 8.1CVE-2026-53783

rsync < 3.5.0 TOCTOU Race Condition Directory Escape via rrsync

Answer in brief

CVE-2026-53783 records a High severity (CVSS 8.1) vulnerability in rsync < 3.5.0 TOCTOU Race Condition Directory Escape via rrsync. The current sources do not mark it as known exploited. The current feed maps RsyncProject/rsync (generic), RsyncProject/rsync (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 13, 2026Updated Sep 8, 2026Source checked Sep 27, 2026First seen by HOL Aug 13, 2026Material review Sep 8, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 8.1
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Not reported

Why this deserves its current priority

CVSS is 8.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps RsyncProject/rsync (generic), RsyncProject/rsync (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
RsyncProject/rsyncgeneric	0	Not reported
RsyncProject/rsyncgeneric	>=0 <=3.4.4	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for RsyncProject/rsync, RsyncProject/rsync.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Aug 13, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 8, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 13, 2026

Sources and claim methodology

Upstream source description

rsync before 3.5.0 contains a time-of-check to time-of-use (TOCTOU) race condition vulnerability in the rrsync restricted shell wrapper that allows authenticated clients to escape enforced directory restrictions by substituting a symlink for a path component after validation but before transfer processing. Attackers can additionally leverage unrestricted flags such as --copy-unsafe-links, -D, and --log-file through rrsync to read or write files outside the permitted directory subtree.

Quoted source text, attributed separately from HOL analysis.