CVE-2026-80603Network attack vector

Incorrect DCC expectations via off-by-one read

Published Aug 28, 2026 · Updated Aug 28, 2026

An out-of-bounds read in the Linux kernel nf_conntrack_irc helper allows remote attackers to create incorrect IRC DCC expectations. The parse_dcc newline loop dereferences data_end even though the caller supplies it as a one-past-the-buffer pointer, letting stale padding bytes enter simple_strtoul parsing. Reachability requires the IRC connection-tracking helper to inspect a crafted DCC message without a newline; the padded allocation prevents a fault, but a stale ASCII digit can corrupt the expected DCC address or port.

CVSS severityUnavailable
Unscored
EPSS probability0.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

An out-of-bounds read in the Linux kernel nf_conntrack_irc helper allows remote attackers to create incorrect IRC DCC expectations. The parse_dcc newline loop dereferences data_end even though the caller supplies it as a one-past-the-buffer pointer, letting stale padding bytes enter simple_strtoul parsing. Reachability requires the IRC connection-tracking helper to inspect a crafted DCC message without a newline; the padded allocation prevents a fault, but a stale ASCII digit can corrupt the expected DCC address or port.

The record

CVE
CVE-2026-80603
Published
Aug 28, 2026
Updated
Aug 28, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 28, 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=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2393f0bd7a467ad475598f3a5b9de27ca36e3037
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2b70f61f569bb29acb380e6f616a1bbdee15668f
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <437e0a3854b3a44ec15afa9ab88ec215adf3a2fd
  4. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <910c33e4a8c046c3cc1fa5a465a4d41a1bb398f1
  5. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <abb8c32b88ea3f46beb68c34fe9a3ac8ed664e7e
  6. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <aff589556ed772cb1c0c2d7b4d91ec45c0c39416
  7. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <eeef3b81f449560653662df2dde6f6fe247c5365
  8. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <ef6400ca25a13fd6dedbe8ef4a1d0979bbbfe88a
  9. Affected versionversion=2.6.12

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2393f0bd7a467ad475598f3a5b9de27ca36e3037; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2b70f61f569bb29acb380e6f616a1bbdee15668f; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <437e0a3854b3a44ec15afa9ab88ec215adf3a2fd; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <910c33e4a8c046c3cc1fa5a465a4d41a1bb398f1; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <abb8c32b88ea3f46beb68c34fe9a3ac8ed664e7e; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <aff589556ed772cb1c0c2d7b4d91ec45c0c39416; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <eeef3b81f449560653662df2dde6f6fe247c5365; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <ef6400ca25a13fd6dedbe8ef4a1d0979bbbfe88a; version=2.6.12

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