CVE-2026-80904Network attack vectorHinoki check available

Unauthenticated record delivery after failed TLS decryption

Published Sep 4, 2026 · Updated Sep 4, 2026

Improper TLS record handling in affected Linux kernel releases starting at 5.19 allows remote attackers to deliver unauthenticated records via splice. The tls_sw_splice_read() path fails to read the persistent ctx->async_wait.err after asynchronous decryption fails, unlike the recvmsg and read_sock paths. Exploitation requires kernel TLS software receive processing, an asynchronous decryption failure, and a splice consumer; the result is delivery of a record that failed authentication.

CVSS severityUnavailable
Unscored
EPSS probability0.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper TLS record handling in affected Linux kernel releases starting at 5.19 allows remote attackers to deliver unauthenticated records via splice. The tls_sw_splice_read() path fails to read the persistent ctx->async_wait.err after asynchronous decryption fails, unlike the recvmsg and read_sock paths. Exploitation requires kernel TLS software receive processing, an asynchronous decryption failure, and a splice consumer; the result is delivery of a record that failed authentication.

The record

CVE
CVE-2026-80904
Published
Sep 4, 2026
Updated
Sep 4, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 4, 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=5.19
  2. Affected versionversion=f314bfee81b1bf8e01168177b2f65f24eb8da63a <06c2a53604fa1dc4820063828d7dadb3675b7af8
  3. Affected versionversion=f314bfee81b1bf8e01168177b2f65f24eb8da63a <18ae1e95f20867106a28820c208a9cec99dda861
  4. Affected versionversion=f314bfee81b1bf8e01168177b2f65f24eb8da63a <4b177911eb9f799e9841c2f87c75b08cb112757a
  5. Affected versionversion=f314bfee81b1bf8e01168177b2f65f24eb8da63a <82d9269f01ebfd835b6256aa17016a974cbbc647
  6. Affected versionversion=f314bfee81b1bf8e01168177b2f65f24eb8da63a <976df67f463db1fddaf2a32fb04f57ad2891a23d
  7. Affected versionversion=f314bfee81b1bf8e01168177b2f65f24eb8da63a <a808aadff634c7a408b2ab84d5919e9a741fdb5b

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.19; version=f314bfee81b1bf8e01168177b2f65f24eb8da63a <06c2a53604fa1dc4820063828d7dadb3675b7af8; version=f314bfee81b1bf8e01168177b2f65f24eb8da63a <18ae1e95f20867106a28820c208a9cec99dda861; version=f314bfee81b1bf8e01168177b2f65f24eb8da63a <4b177911eb9f799e9841c2f87c75b08cb112757a; version=f314bfee81b1bf8e01168177b2f65f24eb8da63a <82d9269f01ebfd835b6256aa17016a974cbbc647; version=f314bfee81b1bf8e01168177b2f65f24eb8da63a <976df67f463db1fddaf2a32fb04f57ad2891a23d; version=f314bfee81b1bf8e01168177b2f65f24eb8da63a <a808aadff634c7a408b2ab84d5919e9a741fdb5b

Published CVSS scores

No CVSS assessment is available in this record.

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

No sourced classifications are available.

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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo