NULL Pointer Dereference Affecting haproxy package, versions [,3.5-dev1)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published28 Jun 2026
- disclosed18 Jun 2026
- creditUnknown
Introduced: 18 Jun 2026
CVE-2026-55204 (opens in a new tab)How to fix?
Upgrade haproxy to version 3.5-dev1 or higher.
Overview
Affected versions of this package are vulnerable to NULL Pointer Dereference in the hpack_dht_insert function when the return value of hpack_dht_defrag is not validated under memory exhaustion conditions. An attacker can cause the application to crash by triggering HPACK dynamic table insertions while the memory pool is exhausted.