Description
rsync 3.1.0 before 3.5.0 contains a signed integer overflow vulnerability in the I/O timeout implementation that allows attackers to permanently disable connection timeouts by injecting MSG_IO_TIMEOUT messages carrying non-positive (zero or negative) values. Attackers can craft malicious MSG_IO_TIMEOUT messages that cause the timeout variable to wrap to a non-positive value, preventing the timeout check from firing and enabling idle or stalled connections to hold daemon slots indefinitely, leading to resource exhaustion.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| RsyncProject | rsync | 3.1.0 – ≤ 3.4.4 | 3.5.0 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | rsync | 3.5.0+ds1-1 | — |
| Debian 13 | rsync | 3.5.0+ds1-0+deb13u1 | — |
| Debian 12 | rsync | 3.5.0+ds1-0+deb12u1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | rsync | No fix yet | — |
| Ubuntu 26.04 LTS | rsync | No fix yet | — |
| Ubuntu 24.04 LTS | rsync | No fix yet | — |
| Ubuntu 22.04 LTS | rsync | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | rsync | No fix yet | — |
| Ubuntu Pro 18.04 LTS | rsync | No fix yet | — |
| Ubuntu Pro 16.04 LTS | rsync | No fix yet | — |
| Ubuntu Pro 14.04 LTS | rsync | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | rsync | 3.2.7-150600.3.24.1 | SUSE-SU-2026:3657-1 |
| SLES 15 SP6 | rsync | 3.2.7-150600.3.24.1 | SUSE-SU-2026:3657-1 |
| SLES 15 SP5 | rsync | 3.2.3-150400.3.34.1 | SUSE-SU-2026:3634-1 |
| SLES 15 SP4 | rsync | 3.2.3-150400.3.34.1 | SUSE-SU-2026:3634-1 |
Show 13 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | rsync | 3.4.1-160000.6.1 | SUSE-SU-2026:23323-1 |
| SLES for SAP 15 SP6 | rsync | 3.2.7-150600.3.24.1 | SUSE-SU-2026:3657-1 |
| SLES for SAP 15 SP5 | rsync | 3.2.3-150400.3.34.1 | SUSE-SU-2026:3634-1 |
| SLES for SAP 15 SP4 | rsync | 3.2.3-150400.3.34.1 | SUSE-SU-2026:3634-1 |
| SLES 16.0 | rsync | 3.4.1-160000.6.1 | SUSE-SU-2026:23323-1 |
| SLE Micro 6.2 | rsync | 3.4.1-160000.6.1 | SUSE-SU-2026:23289-1 |
| SLE Micro 6.1 | rsync | 3.3.0-slfo.1.1_7.1 | SUSE-SU-2026:23254-1 |
| SLE Micro 6.0 | rsync | 3.2.7-8.1 | SUSE-SU-2026:23253-1 |
| SLE Micro 5.5 | rsync | 3.2.3-150400.3.34.1 | SUSE-SU-2026:3634-1 |
| SLE Micro 5.4 | rsync | 3.2.3-150400.3.34.1 | SUSE-SU-2026:3634-1 |
| SLE Micro 5.3 | rsync | 3.2.3-150400.3.34.1 | SUSE-SU-2026:3634-1 |
| SLE HPC 15 SP5 | rsync | 3.2.3-150400.3.34.1 | SUSE-SU-2026:3634-1 |
| SLE HPC 15 SP4 | rsync | 3.2.3-150400.3.34.1 | SUSE-SU-2026:3634-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | rsync | 3.5.1-1.1 | openSUSE-SU-2026:11869-1 |
| openSUSE Leap 16.0 | rsync | 3.4.1-160000.6.1 | openSUSE-SU-2026:21650-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | rsync | 3.5.0-r0 | — |
| Alpine v3.23 | rsync | 3.5.0-r0 | — |
| Alpine v3.22 | rsync | 3.5.0-r0 | — |
| Alpine v3.21 | rsync | 3.5.0-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | rsync +1 | 3.5.1-1.amzn2023.0.1 | ALAS2023-2026-3131 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | rsync | 3.5.0-1 | — |
Advisories 10
- WID-SEC-2026-2817 Rsync: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 8, 2026
- ALAS2023-2026-3131 Important: rsync security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Sep 28, 2026
- openSUSE-SU-2026:11869-1 rsync-3.5.1-1.1 on GA media SUSE / openSUSE Security Updates · Sep 24, 2026
- SUSE-SU-2026:23323-1 Security update for rsync SUSE / openSUSE Security Updates · Sep 10, 2026
- SUSE-SU-2026:23289-1 Security update for rsync SUSE / openSUSE Security Updates · Sep 4, 2026
- SUSE-SU-2026:23254-1 Security update for rsync SUSE / openSUSE Security Updates · Aug 31, 2026
- SUSE-SU-2026:23253-1 Security update for rsync SUSE / openSUSE Security Updates · Aug 27, 2026
- openSUSE-SU-2026:21650-1 Security update for rsync SUSE / openSUSE Security Updates · Aug 27, 2026
- SUSE-SU-2026:3657-1 Security update for rsync SUSE / openSUSE Security Updates · Aug 21, 2026
- SUSE-SU-2026:3634-1 Security update for rsync SUSE / openSUSE Security Updates · Aug 18, 2026
References
- GitHub Security Advisory (GHSA-j9wh-5jmp-2m64) vendor-advisory
- rsync 3.5.0 Release Notes release-notes
- https://www.vulncheck.com/advisories/rsync-signed-integer-overflow-via-msg-io-timeout third-party-advisory