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TI-2026-32781 Aliases CVE-2026-44909GHSA-p9xj-3649-7qp8

Proxygen lacked a generalized slow-consumer detection mechanism in its core HTTP session…

Priority MEDIUM 40Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00573 47th percentileScored 2026-11-07
Fix Fixed proxygen (Facebook): v2026.07.20.00

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Metaproxygenv2017.01.16.00 to before v2026.07.20.00v2026.07.20.00Patch availableCNA
  • proxygen VendorMeta Affected v2017.01.16.00 to before v2026.07.20.00 Fixed in v2026.07.20.00 Patch available CNA

Remediation

  • Fix · CNA proxygen (Facebook) Fixed in v2026.07.20.00

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-44909
  2. 2026-10-03 Alias added: GHSA-p9xj-3649-7qp8

References

  • TI-2025-34861 Deserialization of untrusted data in Meta react-server-dom-webpack KEVCVSS 3.1CRITICAL 10.0
  • TI-2019-02633 Heap-based buffer overflow in Meta WhatsApp for Android KEVCVSS 3.1CRITICAL 9.8
  • TI-2019-13416 Cross-site scripting in Meta WhatsApp Desktop KEVCVSS 3.1HIGH 8.2
  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
  • TI-2025-34857 Incorrect authorization in Meta WhatsApp Desktop for Mac KEVCVSS 3.1MEDIUM 5.4
  • TI-2025-34863 Deserialization of untrusted data in Meta react-server-dom-webpack CVSS 3.1HIGH 7.5
See all 191 →

Sources