CVE-2026-15709Public exploitNetwork attack vector

Remote application crash via unbounded WebSocket decompression

Published Jul 14, 2026 · Updated Jul 14, 2026

Improper compressed-data handling in libsoup WebSockets on Red Hat Enterprise Linux 8 through 10 allows remote attackers to crash applications. The permessage-deflate inflate() loop grows its output buffer without a limit, while the total-message-size check runs only after decompression and is disabled by default for clients. Unauthenticated network access to a client or server application negotiating that extension is sufficient to exhaust memory and terminate the process.

CVSS severity7.5
High
EPSS probability0.55%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper compressed-data handling in libsoup WebSockets on Red Hat Enterprise Linux 8 through 10 allows remote attackers to crash applications. The permessage-deflate inflate() loop grows its output buffer without a limit, while the total-message-size check runs only after decompression and is disabled by default for clients. Unauthenticated network access to a client or server application negotiating that extension is sufficient to exhaust memory and terminate the process.

The record

CVE
CVE-2026-15709
Published
Jul 14, 2026
Updated
Jul 14, 2026
Vendor
389 Directory Server
Product
Red Hat Enterprise Linux 10
Classifications
CWE-409, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 14, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 14, 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?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

389 Directory Server · Red Hat Enterprise Linux 10Affected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 9Affected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 8Affected versions are unavailable in this record.

Published CVSS scores

7.5Red HatCVSS: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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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 exploitPublished

Weakness, pattern, technique

CWE-409Improper Handling of Highly Compressed Data (Data Amplification)
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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