CVE-2026-55203
A remote, anonymous attacker can exploit multiple vulnerabilities in HAProxy to manipulate files or cause a Denial of Service.
CSIRTS triage
- What
- A remote, anonymous attacker can exploit multiple vulnerabilities in HAProxy to manipulate files or cause a Denial of Service.
- Who is affected
- Deployments of HAProxy are affected.
- Urgency
- Remediation is urgent due to the high severity and potential for significant impact.
- Action
- Update HAProxy to the latest version to mitigate these vulnerabilities.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Low exploitation risk0.32% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 24% of all EPSS-scored CVEs.
Advisory coverage (2)
- high[UPDATE] [high] HAProxy: Multiple vulnerabilitiescert-bund · 2026-07-09
- highCVE-2026-55203: HAProxy - Integer Overflow in FCGI Demux Record Length Fieldmsrc · 2026-06-09
External references
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