CVE-2026-72330Network attack vector

Connection denial of service via empty TLS records

Published Aug 15, 2026 · Updated Aug 15, 2026

Denial of service in the Linux kernel TLS receive path allows remote attackers to stall a connection with empty TLS 1.3 records. In tls_sw_read_sock(), the read actor returns zero for a decrypted zero-length application-data record, which the loop mistakes for backpressure and requeues at the head of rx_list. The affected path requires kernel TLS receive processing; the stuck record then blocks every later record on that connection.

CVSS severity7.5
High
EPSS probability0.63%
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 the Linux kernel TLS receive path allows remote attackers to stall a connection with empty TLS 1.3 records. In tls_sw_read_sock(), the read actor returns zero for a decrypted zero-length application-data record, which the loop mistakes for backpressure and requeues at the head of rx_list. The affected path requires kernel TLS receive processing; the stuck record then blocks every later record on that connection.

The record

CVE
CVE-2026-72330
Published
Aug 15, 2026
Updated
Aug 15, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-835, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=6.6
  2. Affected versionversion=662fbcec32f4af6bdcf5b4006b792ebe9543d945 <0867b0f2513ebc1c475af9898c97f4772a68d964
  3. Affected versionversion=662fbcec32f4af6bdcf5b4006b792ebe9543d945 <3be28e2c9cd0230cb51fd4967df095273afd3848
  4. Affected versionversion=662fbcec32f4af6bdcf5b4006b792ebe9543d945 <c6b440cf766a557b08d25f1b571b3d57d039686e
  5. Affected versionversion=662fbcec32f4af6bdcf5b4006b792ebe9543d945 <e8a4c9fc437b16aef38f86ce3275677e36924259
  6. Affected versionversion=662fbcec32f4af6bdcf5b4006b792ebe9543d945 <ebc295ce343600c2d60c1e1e0c5d192080217457

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=6.6; version=662fbcec32f4af6bdcf5b4006b792ebe9543d945 <0867b0f2513ebc1c475af9898c97f4772a68d964; version=662fbcec32f4af6bdcf5b4006b792ebe9543d945 <3be28e2c9cd0230cb51fd4967df095273afd3848; version=662fbcec32f4af6bdcf5b4006b792ebe9543d945 <c6b440cf766a557b08d25f1b571b3d57d039686e; version=662fbcec32f4af6bdcf5b4006b792ebe9543d945 <e8a4c9fc437b16aef38f86ce3275677e36924259; version=662fbcec32f4af6bdcf5b4006b792ebe9543d945 <ebc295ce343600c2d60c1e1e0c5d192080217457

Published CVSS scores

5.5Red HatCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
7.5CVE.orgCVSS: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 exploitUnconfirmed

Weakness, pattern, technique

CWE-835Loop with Unreachable Exit Condition ('Infinite Loop')
T1499.004Application or System Exploitation DoS

Public exploit references

No public exploit references are available in this record.

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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