Description
A flaw was found in iperf3. A remote unauthenticated attacker can exploit a vulnerability in the `JSON_read()` function, which accepts a peer-controlled message length and allocates memory without an upper bound. This allows the attacker to trigger excessive memory consumption, leading to a Denial of Service (DoS) through memory exhaustion, severe slowdown, or termination of the iperf3 service.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | — | — |
| Red Hat | Red Hat Enterprise Linux 7 | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — |
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 | iperf3 | 3.18-1 | — |
| Debian 13 | iperf3 | 3.18-1 | — |
| Debian 12 | iperf3 | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 24.04 LTS | iperf3 | No fix yet | — |
| Ubuntu Pro 22.04 LTS | iperf3 | No fix yet | — |
| Ubuntu Pro 20.04 LTS | iperf3 | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | iperf3 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | iperf3 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | iperf | 3.22-150000.3.18.1 | SUSE-SU-2026:4678-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | iperf | 3.21-160000.1.1 | SUSE-SU-2026:24234-1 |
| SLES 16.0 | iperf | 3.21-160000.1.1 | SUSE-SU-2026:24234-1 |
| SLE Micro 6.2 | iperf | 3.21-160000.1.1 | SUSE-SU-2026:24178-1 |
| SUSE Enterprise Storage 7.1 | iperf | 3.22-150000.3.18.1 | SUSE-SU-2026:4678-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | iperf | 3.22-1.1 | openSUSE-SU-2026:12060-1 |
| openSUSE Leap 16.0 | iperf | 3.21-160000.1.1 | openSUSE-SU-2026:22090-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | iperf3 | 3.17.1-5 | — |
Advisories 5
- SUSE-SU-2026:24234-1 Security update for iperf SUSE / openSUSE Security Updates · Oct 21, 2026
- SUSE-SU-2026:24178-1 Security update for iperf SUSE / openSUSE Security Updates · Oct 20, 2026
- openSUSE-SU-2026:22090-1 Security update for iperf SUSE / openSUSE Security Updates · Oct 19, 2026
- SUSE-SU-2026:4678-1 Security update for iperf SUSE / openSUSE Security Updates · Oct 15, 2026
- openSUSE-SU-2026:12060-1 iperf-3.22-1.1 on GA media SUSE / openSUSE Security Updates · Oct 6, 2026