# CVE-2026-53799: rsync < 3.5.0 Symlink Race Condition via ACL/xattr Application

> Local attackers can exploit a symlink race condition in rsync to apply arbitrary ACLs or extended attributes to unintended files, potentially leading to privilege escalation.

- **Severity:** High 7.2 (`CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 13 Aug 2026
- **Updated:** 14 Aug 2026
- **Also known as:** ALPINE-CVE-2026-53799, AZL-95849, BELL-CVE-2026-53799, CLSA-2026-1789554695, DEBIAN-CVE-2026-53799, ECHO-641e-898c-c057, GHSA-phxh-hjqv-39c9, UBUNTU-CVE-2026-53799

## What is CVE-2026-53799?

CVE-2026-53799 is a high-severity vulnerability in RsyncProject rsync, published on 13 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

rsync before 3.5.0 contains a symlink race condition vulnerability that allows local attackers to cause rsync to apply arbitrary ACLs or extended attributes to unintended files by substituting a symlink at a predictable destination path between the file write and the subsequent acl_set_file() or lsetxattr() call. Attackers can exploit this timing window to redirect ACL and xattr application through a crafted symlink to files outside the intended destination tree, potentially granting elevated permissions and enabling local privilege escalation.

Weakness: CWE-59 (Improper Link Resolution Before File Access), CWE-367 (Time-of-check Time-of-use (TOCTOU) Race Condition)

## Which versions are affected by CVE-2026-53799?

It affects 1 product.


Products: Samba Rsync.

## How do I fix CVE-2026-53799?

Upgrade to a fixed version.

## Is CVE-2026-53799 being exploited?

There is no known exploitation of CVE-2026-53799 in the wild and no public exploit code.

## Other vulnerabilities in RsyncProject rsync

- [CVE-2017-15994](https://insights.sbomify.com/CVE-2017-15994/): Security feature bypass in n/a (critical 9.8)
- [CVE-2026-53791](https://insights.sbomify.com/CVE-2026-53791/): rsync < 3.5.0 Daemon IP Spoofing via PROXY Protocol Header (critical 9.1)
- [CVE-2026-70461](https://insights.sbomify.com/CVE-2026-70461/): rsync 3.2.5 < 3.5.0 Heap Out-of-Bounds Write via files-from Entry (high 8.8)
- [CVE-2026-70455](https://insights.sbomify.com/CVE-2026-70455/): rsync 3.4.2 < 3.5.0 DoS via --zt Zstandard Compression Thread Exhaustion (high 8.7)
- [CVE-2026-70463](https://insights.sbomify.com/CVE-2026-70463/): rsync 3.1.0 < 3.5.0 Authorization Bypass via auth users Directive Parsing (high 8.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-53799 and fix it if it is affected.

What it is: CVE-2026-53799 is a high-severity vulnerability in RsyncProject rsync, published on 13 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-53799 in the wild and no public exploit code.

Affected product: RsyncProject rsync. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-53799/ (Markdown: https://insights.sbomify.com/CVE-2026-53799/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53799
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53799
- OSV: https://osv.dev/vulnerability/CVE-2026-53799

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53799/
Summaries are generated and may contain mistakes; the official description above is the record.