CVE-2026-114458
MediumCVSS 5.9Exploitation Probability (EPSS)
Low risk23th percentile - higher than 23% of all known CVEs
Summary
A flaw was found in mod_qos that allows an unauthenticated remote attacker to 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, leading to heap memory corruption and a crash of the web server process.
Risk Assessment
An attacker can remotely cause heap memory corruption and crash the Apache server, resulting in service unavailability. The vulnerability is easy to trigger by maintaining many slow connections.
Recommendation
Upgrade mod_qos to a version containing the array boundary verification fix. Until then, consider disabling connection rate monitoring or limiting concurrent connections at the proxy level.
Other vulnerabilities in mod_qos
See all- CVE-2026-114460Medium
A flaw was found in mod_qos. An off-by-one pointer calculation error occurs when merging request body parameters with an existing URL query, which truncates the query string during security evaluation while leaving the actual request unchanged. An unauthenticated remote attacker could exploit this vulnerability by submitting a crafted request that conceals prohibited values from inspection, resulting in a bypass of configured security rules.
- CVE-2026-114459Low
A flaw was found in mod_qos where improper boundary checking when inspecting HTTP response bodies causes the module to read memory outside allocated buffer boundaries. An unauthenticated remote attacker can exploit this by triggering specially crafted server responses, crashing an Apache worker process and causing a Denial of Service (DoS).
- CVE-2026-114457Low
A flaw was found in mod_qos that allows an unauthenticated remote attacker to cause a Denial of Service (DoS) by sending a specially crafted JSON request when JSON body filtering is enabled. Due to improper string termination during processing of percent-encoded input, the module reads past allocated memory boundaries, which can crash an Apache worker process.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS