CVE-2026-44909 (GCVE-0-2026-44909)

Vulnerability from cvelistv5 – Published: 2026-07-23 16:27 – Updated: 2026-07-23 19:07
VLAI
Summary
Proxygen lacked a generalized slow-consumer detection mechanism in its core HTTP session layer. A remote, unauthenticated attacker could exploit HTTP/2 flow-control by setting SETTINGS_INITIAL_WINDOW_SIZE to 0 or withholding WINDOW_UPDATE frames, causing the server to buffer complete response bodies in memory indefinitely for stalled streams. By opening many simultaneous streams requesting large resources while preventing the server from transmitting responses, an attacker could induce unbounded memory growth leading to service degradation, resource exhaustion, or denial of service. Versions v2017.01.16.00 through v2026.07.20.00 are affected.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-23 19:07 UTC
CWE
Assigner
Meta CNA under the mitre root
CNA scorecard D 47/100 over 10 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Facebook proxygen Affected: v2017.01.16.00 , < v2026.07.20.00 (semver)
guessed Create a notification for this product.
Show details on NVD website
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