Description
OpenResty lua-resty-dns before 0.24 contains an improper input validation vulnerability in parse_section() and _decode_name() that fails to check resource record lengths against the received message. Attackers controlling or spoofing a queried nameserver can send truncated record headers or RDATA, raising uncaught Lua exceptions in resolver:query() that abort requests and break name resolution.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| openresty | lua-resty-dns | < 0.24 | 0.24 |
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 | lua-nginx-dns | No fix yet | — |
| Debian 13 | lua-nginx-dns | No fix yet | — |
| Debian 12 | lua-nginx-dns | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | lua-nginx-dns | No fix yet | — |
| Ubuntu 26.04 LTS | lua-nginx-dns | No fix yet | — |
| Ubuntu 24.04 LTS | lua-nginx-dns | No fix yet | — |
| Ubuntu 22.04 LTS | lua-nginx-dns | No fix yet | — |
| Ubuntu 20.04 LTS | lua-nginx-dns | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | lua-nginx-dns | No fix yet | — |
| Ubuntu 16.04 LTS | lua-nginx-dns | No fix yet | — |
References
- https://github.com/openresty/lua-resty-dns/pull/83 patch issue-tracking
- https://github.com/openresty/lua-resty-dns/commit/b68eaecbf7997ac71c08ba56032b1f45438bd758 patch
- https://github.com/openresty/lua-resty-dns/blob/v0.23/lib/resty/dns/resolver.lua#L396-L442 technical-description
- https://github.com/openresty/lua-resty-dns/tree/v0.24 release-notes
- VulnCheck Advisory: OpenResty lua-resty-dns before 0.24 Denial of Service via DNS Response Parsing third-party-advisory