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TI-2026-61879 Aliases CVE-2026-91095GHSA-c3mh-7h6x-xh3f

Use after free in Meta proxygen

Priority LOW 30CWE-416Published · Updated

Key facts

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

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

Summary

In proxygen from v2024.10.28.00 until v2026.09.28.00, the HTTPTransaction::onWebTransportUniStream and HTTPTransaction::onWebTransportBidiStream APIs could return stream handles that the stream handler had already freed. HQSession then installed those handles as transport read callbacks, which could lead to use of freed memory.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00247 16th percentileScored 2026-11-07
Fix Fixed proxygen (Facebook): v2026.09.28.00

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
Metaproxygenv2024.10.28.00 to before v2026.09.28.00v2026.09.28.00Patch availableCNA
  • proxygen VendorMeta Affected v2024.10.28.00 to before v2026.09.28.00 Fixed in v2026.09.28.00 Patch available CNA

Remediation

  • Fix · CNA proxygen (Facebook) Fixed in v2026.09.28.00

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Facebook proxygen v2026.09.28.00

    3 records Highest priority Priority LOW 3 LOW

    Other records, highest priority first

    Show all 3 records →

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-2026-91095
  2. 2026-10-03 Alias added: GHSA-c3mh-7h6x-xh3f

References

Other 2

  • 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

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences