CVE-2026-114213

Source
https://cve.org/CVERecord?id=CVE-2026-114213
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-114213.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-114213
Aliases
Downstream
Published
2026-10-26T13:30:58Z
Modified
2026-10-28T02:56:11Z
Severity
  • 8.7 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVSS Calculator
Summary
WebSocket 1-byte continuation frames bypass `max_fragmented_message_size` in Bandit
Details

Allocation of Resources Without Limits or Throttling vulnerability in the WebSocket fragment reassembly of mtrudel bandit allows an unauthenticated remote attacker to exhaust server memory via a fragmented message made of many 1-byte continuation frames.

Bandit.WebSocket.Connection checks max_fragmented_message_size against the payload bytes received, but keeps every non-final continuation frame as a new list cell around its own binary, and nothing limits the number of fragments. A 1-byte fragment costs 7 bytes on the wire but about 150 to 170 bytes of server memory, so one connection can hold about 150 times the configured limit, roughly 1.2 to 1.4 GB at the default 8 MB. Ping frames between fragments keep the connection alive past the idle timeout.

This issue affects bandit: from 1.11.0 before 1.14.0.

Database specific
{
    "cna_assigner": "EEF",
    "cwe_ids": [
        "CWE-770"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/114xxx/CVE-2026-114213.json"
}
References

Affected packages

Git / github.com/mtrudel/bandit

Affected ranges

Type
GIT
Repo
https://github.com/mtrudel/bandit
Events
Database specific
Show details
{
    "extracted_events": [
        {
            "range": [
                {
                    "introduced": "21612c7c7b1ce43eccd36d3af3a2299d23513667"
                },
                {
                    "fixed": "220b9dfd27f9a21305be2afc75cbe585ddc24e7a"
                }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StandardRange"
        },
        {
            "range": [
                {
                    "introduced": "1.11.0"
                },
                {
                    "fixed": "1.14.0"
                }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StandardRange"
        },
        {
            "range": [
                {
                    "fixed": "21612c7c7b1ce43eccd36d3af3a2299d23513667"
                }
            ],
            "source": "REFERENCES_COMMIT"
        },
        {
            "range": [
                {
                    "fixed": "220b9dfd27f9a21305be2afc75cbe585ddc24e7a"
                }
            ],
            "source": "REFERENCES_COMMIT"
        }
    ]
}

Affected versions

1.*
1.11.0
1.11.1
1.12.0
1.12.1
1.12.3
1.12.4
1.12.5
1.13.0
1.13.1

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-114213.json"