Description
lldpd is an implementation of IEEE 802.1ab (LLDP). Prior to version 1.0.22, lldpd_decode() in src/daemon/lldpd.c strips 802.1Q VLAN tags from received Ethernet frames by calling memmove() to shift the frame payload 4 bytes left. The third argument (byte count) is s - 2 * ETHER_ADDR_LEN but should be s - 2 * ETHER_ADDR_LEN - 4, causing a 4-byte heap buffer over-read past the malloc(h_mtu) allocation when the received frame size equals the interface MTU. This issue has been patched in version 1.0.22.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| lldpd | lldpd | < 1.0.22 | — |
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 | lldpd | 1.0.22-1 | — |
| Debian 13 | lldpd | No fix yet | — |
| Debian 12 | lldpd | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | lldpd +1 | No fix yet | — |
| Ubuntu 26.04 LTS | lldpd +1 | No fix yet | — |
| Ubuntu 25.10 | lldpd +1 | No fix yet | — |
| Ubuntu 24.04 LTS | lldpd +1 | No fix yet | — |
| Ubuntu 22.04 LTS | lldpd +1 | No fix yet | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | lldpd +1 | No fix yet | — |
| Ubuntu 18.04 LTS | lldpd | No fix yet | — |
| Ubuntu 16.04 LTS | lldpd | No fix yet | — |
| Ubuntu Pro 18.04 LTS | openvswitch | No fix yet | — |
| Ubuntu Pro 16.04 LTS | openvswitch | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | lldpd | 1.0.22-1.1 | openSUSE-SU-2026:10794-1 |
| openSUSE Leap 16.0 | lldpd | 1.0.22-bp160.1.1 | openSUSE-SU-2026:21146-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | lldpd | 1.0.22-r0 | — |
| Alpine v3.23 | lldpd | 1.0.22-r0 | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | lldpd | 1.0.22-1 | — |
Advisories 2
- openSUSE-SU-2026:21146-1 Security update for lldpd SUSE / openSUSE Security Updates · Jun 30, 2026
- openSUSE-SU-2026:10794-1 liblldpctl4-1.0.22-1.1 on GA media SUSE / openSUSE Security Updates · May 17, 2026