CVE-2026-10725Network attack vector

Unauthenticated denial of service via HPACK expansion

Published Jun 6, 2026 · Updated Jun 6, 2026

Denial of service in Protocol::HTTP2 before 1.13 allows remote attackers to crash or severely slow server processes with compressed headers. The inbound HPACK decoder copies each expanded header without enforcing its advertised size limit, while continuation data can also accumulate without a bound. Any network-reachable server using the module can exhaust process memory, causing a crash or substantial slowdown.

CVSS severity7.5
High
EPSS probability0.41%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Protocol::HTTP2 before 1.13 allows remote attackers to crash or severely slow server processes with compressed headers. The inbound HPACK decoder copies each expanded header without enforcing its advertised size limit, while continuation data can also accumulate without a bound. Any network-reachable server using the module can exhaust process memory, causing a crash or substantial slowdown.

The record

CVE
CVE-2026-10725
Published
Jun 6, 2026
Updated
Jun 6, 2026
Vendor
The Perl Foundation
Product
Protocol::HTTP2
Classifications
CWE-409, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 6, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 6, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=0 <=1.12

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Perl Foundation · Protocol::HTTP2version=0 <=1.12

Published CVSS scores

7.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-409Improper Handling of Highly Compressed Data (Data Amplification)
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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