Description
An uncontrolled resource consumption (memory leak) flaw was found in ZeroMQ's src/xpub.cpp in versions before 4.3.3. This flaw allows a remote unauthenticated attacker to send crafted PUB messages that consume excessive memory if the CURVE/ZAP authentication is disabled on the server, causing a denial of service. The highest threat from this vulnerability is to system availability.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | zeromq | zeromq 4.3.3 | — |
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 | zeromq3 | 4.3.3-1 | — |
| Debian 13 | zeromq3 | 4.3.3-1 | — |
| Debian 12 | zeromq3 | 4.3.3-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | zeromq3 | 4.3.2-2ubuntu1.20.04.1~esm2 | USN-4920-1 |
| Ubuntu Pro 18.04 LTS | zeromq3 | 4.2.5-1ubuntu0.2+esm2 | USN-4920-1 |
| Ubuntu Pro 16.04 LTS | zeromq3 | 4.1.4-7ubuntu0.1+esm2 | USN-4920-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 14.04 LTS | zeromq3 | 4.0.4+dfsg-2ubuntu0.1+esm3 | USN-4920-1 |
Advisories 1
- USN-4920-1 zeromq3 vulnerabilities Ubuntu Security Notices (USN) · Jun 29, 2026