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TI-2026-79300 Aliases CVE-2026-115482GHSA-mhr4-9xv4-xpwf

Unlimited buffered header sets in lsquic HTTP/3 exhaust memory

Priority LOW 39CWE-770Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-770.

Summary

In lsquic before 4.9.0, the HTTP/3 implementation does not limit the number of buffered header sets. A remote attacker can use a QPACK amplification attack to make the server consume an excessive amount of memory, as CWE-770 describes.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

In lsquic before 4.9.0, the HTTP/3 implementation can use an excessive amount of memory because the number of buffered header sets is not limited, as demonstrated by a QPACK amplification attack. This is related to header_out_dynamic_entry and es_max_header_list_size.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00446 39th percentileScored 2026-11-07
Fix Fixed lsquic (litespeedtech): 4.9.0

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
litespeedtechlsquicbefore 4.9.04.9.0Patch availableCNA
  • lsquic Vendorlitespeedtech Affected before 4.9.0 Fixed in 4.9.0 Patch available CNA

Remediation

Upgrade lsquic to version 4.9.0.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA lsquic (litespeedtech) Fixed in 4.9.0

Timeline

  1. 2026-10-22 Threatist record created from CVE-2026-115482
  2. 2026-10-22 CISA SSVC decision points changed
  3. 2026-10-22 Priority changed: MEDIUM → LOW
  4. 2026-10-22 Alias added: GHSA-mhr4-9xv4-xpwf

References

Other 3

  • TI-2026-35606 LiteSpeed User-End cPanel Plugin before 2.4.5 allows privilege escalation (possibly to… KEVCVSS 4.0CRITICAL 10.0
  • TI-2026-39296 LiteSpeed cPanel plugin before 2.4.8 (as distributed in LiteSpeed WHM PlugIn before… KEVCVSS 3.1HIGH 8.5
  • TI-2024-29589 WordPress LiteSpeed Cache plugin < 6.5.0.1 - Unauthenticated Account Takeover via Cookie Leak vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2024-18601 WordPress LiteSpeed Cache plugin <= 6.3.0.1 - Unauthenticated Privilege Escalation vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2022-00030 Authenticated Remote Code Execution in OpenLiteSpeed Web Server CVSS 3.1HIGH 8.8
  • TI-2026-83023 Client certificate bypass over HTTP/3 in OpenLiteSpeed CVSS 4.0HIGH 8.2
See all 46 →

Sources

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