Description
In Kamailio before 5.0.7 and 5.1.x before 5.1.4, a crafted SIP message with a double "To" header and an empty "To" tag causes a segmentation fault and crash. The reason is missing input validation in the "build_res_buf_from_sip_req" core function. This could result in denial of service and potentially the execution of arbitrary code.
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 | kamailio | 5.1.4-1 | — |
| Debian 13 | kamailio | 5.1.4-1 | — |
| Debian 12 | kamailio | 5.1.4-1 | — |
| Debian 9 | kamailio | 4.4.4-2+deb9u2 | DSA-4267-1 |
| Debian 8 | kamailio | 4.2.0-2+deb8u4 | DLA-1471-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | kamailio | 5.3.2-1ubuntu0.1~esm2 | USN-7416-1 |
| Ubuntu Pro 18.04 LTS | kamailio | 5.1.2-1ubuntu2+esm2 | USN-7416-1 |
| Ubuntu Pro 16.04 LTS | kamailio | 4.3.4-1.1ubuntu2.1+esm2 | USN-7416-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | kamailio | 5.1.4-r0 | — |
| Alpine v3.23 | kamailio | 5.1.4-r0 | — |
| Alpine v3.22 | kamailio | 5.1.4-r0 | — |
| Alpine v3.21 | kamailio | 5.1.4-r0 | — |
| Alpine v3.20 | kamailio | 5.1.4-r0 | — |
Show 14 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | kamailio | 5.1.4-r0 | — |
| Alpine v3.18 | kamailio | 5.1.4-r0 | — |
| Alpine v3.17 | kamailio | 5.1.4-r0 | — |
| Alpine v3.16 | kamailio | 5.1.4-r0 | — |
| Alpine v3.15 | kamailio | 5.1.4-r0 | — |
| Alpine v3.14 | kamailio | 5.1.4-r0 | — |
| Alpine v3.13 | kamailio | 5.1.4-r0 | — |
| Alpine v3.12 | kamailio | 5.1.4-r0 | — |
| Alpine v3.11 | kamailio | 5.1.4-r0 | — |
| Alpine v3.10 | kamailio | 5.1.4-r0 | — |
| Alpine v3.9 | kamailio | 5.1.4-r0 | — |
| Alpine v3.8 | kamailio | 5.1.4-r0 | — |
| Alpine v3.7 | kamailio | 5.1.4-r0 | — |
| Alpine v3.6 | kamailio | 5.0.2-r4 | — |
Advisories 3
- USN-7416-1 kamailio vulnerabilities Ubuntu Security Notices (USN) · Jun 25, 2026
- DSA-4267-1 kamailio - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1471-1 kamailio - security update Debian Security (DSA / DLA) · Mar 9, 2026