Description
radvd is a router advertisement daemon for IPv6. Prior to version 2.21, the `radvdump` utility shipped with radvd contains a stack buffer overflow in the Route Information option parser. When processing a crafted ICMPv6 Router Advertisement, `print_ff()` copies up to 2032 bytes from attacker-controlled packet data into a 16-byte `struct in6_addr` on the stack, overflowing by up to 2016 bytes. Note that the main `radvd` daemon is not affected by the vulnerability. Version 2.21 patches the issue.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| radvd-project | radvdump | < 2.21 | — |
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 | radvd | No fix yet | — |
| Debian 13 | radvd | No fix yet | — |
| Debian 12 | radvd | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | radvd | No fix yet | — |
| Ubuntu 26.04 LTS | radvd | No fix yet | — |
| Ubuntu 25.10 | radvd | No fix yet | — |
| Ubuntu 24.04 LTS | radvd | No fix yet | — |
| Ubuntu 22.04 LTS | radvd | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | radvd | No fix yet | — |
| Ubuntu 18.04 LTS | radvd | No fix yet | — |
| Ubuntu 16.04 LTS | radvd | No fix yet | — |
| Ubuntu 14.04 LTS | radvd | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | radvd | 2.17-150000.5.8.1 | SUSE-SU-2026:3055-1 |
| SLES 15 SP6 | radvd | 2.17-150000.5.8.1 | SUSE-SU-2026:3055-1 |
| SLES 15 SP5 | radvd | 2.17-150000.5.8.1 | SUSE-SU-2026:3055-1 |
| SLES 15 SP4 | radvd | 2.17-150000.5.8.1 | SUSE-SU-2026:3055-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | radvd | 2.21-160000.1.1 | SUSE-SU-2026:22836-1 |
| SLES for SAP 15 SP6 | radvd | 2.17-150000.5.8.1 | SUSE-SU-2026:3055-1 |
| SLES for SAP 15 SP5 | radvd | 2.17-150000.5.8.1 | SUSE-SU-2026:3055-1 |
| SLES for SAP 15 SP4 | radvd | 2.17-150000.5.8.1 | SUSE-SU-2026:3055-1 |
| SLES 16.0 | radvd | 2.21-160000.1.1 | SUSE-SU-2026:22836-1 |
| SLE HPC 15 SP5 | radvd | 2.17-150000.5.8.1 | SUSE-SU-2026:3055-1 |
| SLE HPC 15 SP4 | radvd | 2.17-150000.5.8.1 | SUSE-SU-2026:3055-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | radvd | 2.21-1.1 | openSUSE-SU-2026:11161-1 |
| openSUSE Leap 16.0 | radvd | 2.21-160000.1.1 | openSUSE-SU-2026:21400-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | radvd | 2.21-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | radvd | 2.19-2.amzn2023.0.3 | ALAS2023-2026-1799 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | radvd | 2.21-1 | — |
Advisories 5
- SUSE-SU-2026:22836-1 Security update for radvd SUSE / openSUSE Security Updates · Jul 28, 2026
- openSUSE-SU-2026:21400-1 Security update for radvd SUSE / openSUSE Security Updates · Jul 24, 2026
- SUSE-SU-2026:3055-1 Security update for radvd SUSE / openSUSE Security Updates · Jul 16, 2026
- openSUSE-SU-2026:11161-1 radvd-2.21-1.1 on GA media SUSE / openSUSE Security Updates · Jul 1, 2026
- ALAS2023-2026-1799 Important: radvd security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jun 8, 2026