CVE-2026-42304

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Source
https://cve.org/CVERecord?id=CVE-2026-42304
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-42304.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2026-42304
Aliases
Downstream
Related
Published
2026-05-13T20:20:29.149Z
Modified
2026-06-18T03:57:01.556353528Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
Twisted: Denial of Service (DoS) in twisted.names via Crafted DNS Compression Pointer Chains
Details

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.

Database specific 
{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42304.json",
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-400",
        "CWE-407"
    ]
}
References

Affected packages

Git / github.com/twisted/twisted

Affected ranges

Type
GIT
Repo
https://github.com/twisted/twisted
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
3dc92b79333c231338390c2b8cec5c142a31863d
Database specific 
{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "26.4.0"
        },
        {
            "last_affected": "26.4.0-rc1"
        }
    ],
    "cpe": [
        "cpe:2.3:a:twisted:twisted:*:*:*:*:*:*:*:*",
        "cpe:2.3:a:twisted:twisted:26.4.0:rc1:*:*:*:*:*:*"
    ],
    "source": [
        "CPE_RANGE",
        "CPE_STRING"
    ]
}

Affected versions

Other
before-black
twisted-26.*
twisted-26.4.0rc1
twisted-26.4.0rc2

Database specific

source 
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-42304.json"