Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.4.0rc2, the twisted.names module is vulnerable to a Denial of Service (DoS) attack via resource exhaustion during DNS name decompression. A remote, unauthenticated attacker can exploit this by sending a crafted TCP DNS packet containing deeply chained compression pointers. This flaw bypasses previous loop-prevention logic, causing the single-threaded Twisted reactor to hang while processing millions of recursive lookups, effectively freezing the server. This vulnerability is fixed in 26.4.0rc2.

The remote Ubuntu 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS host has a package installed that is affected by a vulnerability as referenced in the USN-8380-1 advisory.

    It was discovered that Twisted incorrectly handled DNS name decompression. A remote attacker could     possibly use this issue to cause Twisted to consume excessive resources, leading to a denial of service.

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The version of CBL-Mariner Releases installed on the remote Azure Linux 3.0 host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the CVE-2026-42304 advisory.

  - Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.4.0rc2,     the twisted.names module is vulnerable to a Denial of Service (DoS) attack via resource exhaustion during     DNS name decompression. A remote, unauthenticated attacker can exploit this by sending a crafted TCP DNS     packet containing deeply chained compression pointers. This flaw bypasses previous loop-prevention logic,     causing the single-threaded Twisted reactor to hang while processing millions of recursive lookups,     effectively freezing the server. This vulnerability is fixed in 26.4.0rc2. (CVE-2026-42304)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

It is, therefore, affected by a vulnerability as referenced in the ALAS2023-2026-1734 advisory.

    The twisted.names module is vulnerable to a Denial of Service (DoS) attack via resource exhaustion during     DNS name decompression. A remote, unauthenticated attacker can exploit this by sending a crafted TCP DNS     packet containing deeply chained compression pointers. This flaw bypasses previous loop-prevention logic,     causing the single-threaded Twisted reactor to hang while processing millions of recursive lookups,     effectively freezing the server. (CVE-2026-42304)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.4.0rc2,     the twisted.names module is vulnerable to a Denial of Service (DoS) attack via resource exhaustion during     DNS name decompression. A remote, unauthenticated attacker can exploit this by sending a crafted TCP DNS     packet containing deeply chained compression pointers. This flaw bypasses previous loop-prevention logic,     causing the single-threaded Twisted reactor to hang while processing millions of recursive lookups,     effectively freezing the server. This vulnerability is fixed in 26.4.0rc2. (CVE-2026-42304)

Note that Nessus relies on the presence of the package as reported by the vendor.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.4.0rc2,
    the twisted.names module is vulnerable to a Denial of Service (DoS) attack via resource exhaustion during
    DNS name decompression. A remote, unauthenticated attacker can exploit this by sending a crafted TCP DNS
    packet containing deeply chained compression pointers. This flaw bypasses previous loop-prevention logic,
    causing the single-threaded Twisted reactor to hang while processing millions of recursive lookups,
    effectively freezing the server. This vulnerability is fixed in 26.4.0rc2. (CVE-2026-42304)

ID	Name	Product	Family	Severity
318626	Ubuntu 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS : Twisted vulnerability (USN-8380-1)	Nessus	Ubuntu Local Security Checks	high
318147	Azure Linux 3.0 Security Update: CBL-Mariner Releases (CVE-2026-42304)	Nessus	Azure Linux Local Security Checks	high
316973	Amazon Linux 2023 : python3-twisted, python3-twisted+tls (ALAS2023-2026-1734)	Nessus	Amazon Linux Local Security Checks	high
314270	Linux Distros Unpatched Vulnerability : CVE-2026-42304	Nessus	Misc.	high
441232	SCA: security update for Twisted (GHSA-grgv-6hw6-v9g4)	Tenable Cloud Security	SCA Checks	high
441232	SCA: security update for Twisted (GHSA-grgv-6hw6-v9g4)	Tenable Self-Hosted Container Security	SCA Checks	high

Detections

Analytics

CVE-2026-42304

high

Tenable Plugins

high

high

high

high

high

high