Description
In FRRouting FRR before 8.5, the service user (usually frr) can escalate its privileges to root by monitoring the configuration directory (/etc/frr) and replacing config files upon creation with, for example, symlinks to change the ownership of arbitrary files. This is a TOCTOU Race Condition caused by a combination of touch and chown.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| FRRouting | FRRouting | < 4.5 | 4.5 |
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 | frr | 8.4.1-1 | — |
| Debian 13 | frr | 8.4.1-1 | — |
| Debian 12 | frr | 8.4.1-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | frr | No fix yet | — |
| Ubuntu 20.04 LTS | quagga | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | frr | No fix yet | — |
| Ubuntu Pro 18.04 LTS | quagga | No fix yet | — |
| Ubuntu Pro 16.04 LTS | quagga | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP4 | frr | 7.4-150300.4.10.1 | SUSE-SU-2022:4130-1 |
| SLES 15 SP3 | frr | 7.4-150300.4.10.1 | SUSE-SU-2022:4130-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | frr | 8.4-1.1 | openSUSE-SU-2024:12516-1 |
| openSUSE Leap 15.4 | frr | 7.4-150300.4.10.1 | SUSE-SU-2022:4130-1 |
| openSUSE Leap 15.3 | frr | 7.4-150300.4.10.1 | SUSE-SU-2022:4130-1 |
Advisories 3
- WID-SEC-2026-3339 FRRouting Project FRRouting: Schwachstelle ermöglicht Privilegieneskalation BSI CERT-Bund (WID) · Sep 13, 2026
- SUSE-SU-2022:4130-1 Security update for frr SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:12516-1 frr-8.4-1.1 on GA media SUSE / openSUSE Security Updates · May 7, 2025