Description
GNU wget is vulnerable to denial of service in its FTP OPIE/S-KEY authentication functionality. The server-supplied sequence number from the FTP challenge line is used as an iteration count for an MD5 key-derivation loop without any upper bound validation. A malicious FTP server or a network attacker positioned to intercept FTP traffic can send a crafted OPIE challenge with a sequence number near INT_MAX, causing wget to perform up to approximately 2.1 billion MD5 computations and suspend for some time. The --timeout option does not mitigate this because it applies only to network I/O, not CPU computation.
This issue was fixed in commit e9697d98e7249b0f68a6be040a4f3dcc5bc101fa
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| GNU | wget | ≤ 1.25.0 | — |
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 | wget | No fix yet | — |
| Debian 13 | wget | No fix yet | — |
| Debian 12 | wget | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | wget | No fix yet | — |
| Ubuntu 26.04 LTS | wget | No fix yet | — |
| Ubuntu 24.04 LTS | wget | No fix yet | — |
| Ubuntu 22.04 LTS | wget | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | wget | No fix yet | — |
| Ubuntu Pro 18.04 LTS | wget | No fix yet | — |
| Ubuntu Pro 16.04 LTS | wget | No fix yet | — |
| Ubuntu Pro 14.04 LTS | wget | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | wget | 1.24.5-150700.3.12.1 | SUSE-SU-2026:4049-1 |
| SLES 12 SP5 | wget | 1.14-21.31.1 | SUSE-SU-2026:4074-1 |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | wget | 1.25.0-160000.4.1 | SUSE-SU-2026:23991-1 |
| SLES 16.0 | wget | 1.25.0-160000.4.1 | SUSE-SU-2026:23991-1 |
| SLE Micro 6.2 | wget | 1.25.0-160000.4.1 | SUSE-SU-2026:23975-1 |
| SLE Micro 6.1 | wget | 1.24.5-slfo.1.1_6.1 | SUSE-SU-2026:23520-1 |
| SLE Micro 6.0 | wget | 1.24.5-5.1 | SUSE-SU-2026:23455-1 |
| SLE Micro 5.5 | wget | 1.20.3-150000.3.40.1 | SUSE-SU-2026:4053-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | wget | 1.25.0-7.1 | openSUSE-SU-2026:11646-1 |
| openSUSE Leap 16.0 | wget | 1.25.0-160000.4.1 | openSUSE-SU-2026:22011-1 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | wget | 1.25.0-r17 | — |
Advisories 10
- SUSE-SU-2026:23991-1 Security update for wget SUSE / openSUSE Security Updates · Oct 6, 2026
- SUSE-SU-2026:23975-1 Security update for wget SUSE / openSUSE Security Updates · Oct 6, 2026
- WID-SEC-2026-3024 wget: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · Oct 4, 2026
- openSUSE-SU-2026:22011-1 Security update for wget SUSE / openSUSE Security Updates · Oct 3, 2026
- SUSE-SU-2026:23520-1 Security update for wget SUSE / openSUSE Security Updates · Sep 15, 2026
- SUSE-SU-2026:23455-1 Security update for wget SUSE / openSUSE Security Updates · Sep 14, 2026
- SUSE-SU-2026:4074-1 Security update for wget SUSE / openSUSE Security Updates · Sep 13, 2026
- SUSE-SU-2026:4049-1 Security update for wget SUSE / openSUSE Security Updates · Sep 13, 2026
- SUSE-SU-2026:4053-1 Security update for wget SUSE / openSUSE Security Updates · Sep 13, 2026
- openSUSE-SU-2026:11646-1 wget-1.25.0-7.1 on GA media SUSE / openSUSE Security Updates · Aug 30, 2026