Description
An exploitable denial-of-service vulnerability exists in the resource allocation handling of Videolabs libmicrodns 0.1.0. When encountering errors while parsing mDNS messages, some allocated data is not freed, possibly leading to a denial-of-service condition via resource exhaustion. An attacker can send one mDNS message repeatedly to trigger this vulnerability through the function rr_read_RR [5] reads the current resource record, except for the RDATA section. This is read by the loop at in rr_read. For each RR type, a different function is called. When the RR type is 0x10, the function rr_read_TXT is called at [6].
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | Videolabs | Videolabs libmicrodns 0.1.0 | — |
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 | libmicrodns | 0.2.0-1 | — |
| Debian 14 | vlc | 3.0.8-4 | — |
| Debian 13 | libmicrodns | 0.2.0-1 | — |
| Debian 13 | vlc | 3.0.8-4 | — |
| Debian 12 | vlc | 3.0.8-4 | — |
| Debian 10 | vlc | 3.0.10-0+deb10u1 | DSA-4671-1 |
| Debian 9 | vlc | 3.0.10-0+deb9u1 | DSA-4671-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | libmicrodns | 0.0.8-1ubuntu0.1~esm1 | USN-7239-1 |
| Ubuntu Pro 18.04 LTS | vlc | 3.0.8-0ubuntu18.04.1+esm3 | — |
Advisories 2
- USN-7239-1 libmicrodns vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DSA-4671-1 vlc - security update Debian Security (DSA / DLA) · Mar 9, 2026
References
- DSA-4671 vendor-advisory
- GLSA-202005-10 vendor-advisory
- https://talosintelligence.com/vulnerability_reports/TALOS-2020-1002