GHSA-h2qv-fj59-j46j: Netty HAProxy: Unbalanced Reference Count in Nested PP2_TYPE_SSL TLV Parsing Leads to Memory Exhaustion

highCVSS 7.5CVE-2026-48059

Impact The HAProxy PROXY protocol v2 codec in netty leaks native or heap memory on every connection when a client sends a syntactically valid header containing nested PP2_TYPE_SSL TLVs (type-length-value records) at depth two or greater. The leak occurs on the successful parse path — no exception is thrown, the message fires downstream, the decoder removes itself, and the application releases the HAProxyMessage normally. Yet the underlying cumulation buffer (a pooled, potentially direct ByteBuf allocated by the channel) remains permanently pinned.

Details

Source: GitHub Security Advisories (INTL · database · site)
Severity: high — CVSS 7.5
Published: 2026-06-11
Last updated: 2026-07-10
Exploitation: Not in CISA KEV at last sync

Original advisory: https://github.com/advisories/GHSA-h2qv-fj59-j46j

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-480590.61% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 45% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-48059	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

high[UPDATE] [high] Netty: Multiple vulnerabilitiescert-bund

GHSA-h2qv-fj59-j46j: Netty HAProxy: Unbalanced Reference Count in Nested PP2_TYPE_SSL TLV Parsing Leads to Memory Exhaustion

Details

Exploitation outlook

Referenced CVEs

Same CVEs, other sources

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