Description
A flaw was found in mod_qos. An unauthenticated remote attacker can cause a Denial of Service (DoS) by maintaining numerous concurrent low-rate connections to a target server. When connection rate monitoring is active, the module fails to verify array boundaries when recording client IP addresses, allowing more connection records to be added than the allocated buffer can hold. This issue leads to heap memory corruption, which can crash the web server process.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| pbuchbinder | mod_qos | 11.74, 11.76, 11.79 | — |
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 | mod-qos | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | mod-qos | No fix yet | — |
| Ubuntu 26.04 LTS | mod-qos | No fix yet | — |
References
- https://access.redhat.com/security/cve/CVE-2026-114458 vdb-entry
- RHBZ#2558393 issue-tracking