CVE-2026-47736 (GCVE-0-2026-47736)
Vulnerability from cvelistv5 – Published: 2026-07-14 19:54 – Updated: 2026-07-15 14:28
VLAI
EPSS
VEX
Title
Puma PROXY Protocol v1 Parser Allows Remote Memory Exhaustion
Summary
Puma is a Ruby/Rack web server built for parallelism. From 5.5.0 until 7.2.1 and 8.0.2, when PROXY protocol v1 support is enabled, Puma reads incoming bytes into an internal buffer while waiting for CRLF to determine whether a PROXY v1 line is present, allowing an attacker that continuously sends bytes without CRLF to cause unbounded in-process memory growth and additional CPU cost from repeatedly scanning the growing buffer. This issue is fixed in versions 7.2.1 and 8.0.2.
Severity
7.5 (High)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-400 - Uncontrolled Resource Consumption
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://github.com/puma/puma/security/advisories/… | x_refsource_CONFIRM |
| https://github.com/puma/puma/commit/439c6136d9c22… | x_refsource_MISC |
| https://github.com/puma/puma/commit/ebe9db3929ab8… | x_refsource_MISC |
| https://github.com/puma/puma/releases/tag/v7.2.1 | x_refsource_MISC |
| https://github.com/puma/puma/releases/tag/v8.0.2 | x_refsource_MISC |
Impacted products
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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