CVE-2026-111808

Apache Traffic Server: HTTP/2 DATA frame padding underflow lets a client trigger backend worker-pool exhaustion

HIGH
8.6
CVSS Score
Published: October 21, 2026 at 07:11 PM UTC
Updated: October 23, 2026 at 10:16 PM UTC
1 product affected across 1 vendorTraffic Server

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Severity
HIGH8.6
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

Description

Apache Traffic Server can be used to exhaust an HTTP/1.1 origin's worker pool via a malformed padded HTTP/2 DATA frame. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.15, from 10.0.0 through 10.1.4, 10.2.0. Users are recommended to upgrade to version 9.2.16, 10.1.5, or 10.2.1, which fix the issue.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.6HIGHapache
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusAWAITING ANALYSIS
CWE
CWE-191

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