CVE-2026-55204
Full vulnerability record from the local CVENow database.
Description
HAProxy through 3.4.0, fixed in commit 9a6d1fe, contains a null pointer dereference vulnerability in hpack_dht_insert() within src/hpack-tbl.c that fails to validate the return value of hpack_dht_defrag() when the memory pool is exhausted. An attacker can trigger HPACK dynamic table insertions under memory pressure to dereference a NULL pointer and crash HAProxy worker processes, causing denial of service.
Severity
HIGH
CVSS score
8.7
(v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-06-18 17:16:34.567000
Last modified
2026-10-26 11:10:00.157000
View original CVE JSON
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"id": "CVE-2026-55204",
"sourceIdentifier": "[email protected]",
"published": "2026-06-18T17:16:34.567",
"lastModified": "2026-10-26T11:10:00.157",
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},
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}
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"source": "[email protected]",
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