CVE-2026-80205

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Source
https://cve.org/CVERecord?id=CVE-2026-80205
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80205.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-80205
Aliases
  • GHSA-rrv8-h7p8-rx55
Downstream
Published
2026-08-26T10:28:14.352Z
Modified
2026-08-28T11:47:33.058686590Z
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
NLTK before 3.10.0 ReDoS via Text.findall() unvalidated regex
Details

NLTK versions before 3.10.0 contain a regular expression denial of service vulnerability in Text.findall() and TokenSearcher.findall() methods that accept user-supplied regular expressions without validation or timeout. Attackers can supply crafted regex patterns that cause catastrophic backtracking, resulting in indefinite CPU saturation and denial of service to all users of the Python process.

Database specific 
{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80205.json",
    "cwe_ids": [
        "CWE-1333"
    ],
    "cna_assigner": "VulnCheck"
}
References

Affected packages

Git / github.com/nltk/nltk

Affected ranges

Type
GIT
Repo
https://github.com/nltk/nltk
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
bd49f9011d7dc8c6a36b3c4ae71f04060c9b3fb9
Database specific
Show details 
{
    "source": [
        "AFFECTED_FIELD",
        "DESCRIPTION"
    ],
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "3.10.0"
        }
    ]
}

Affected versions

2.*
2.0.1rc1
2.0.1rc2
2.0.1rc3
2.0.1rc4
3.*
3.0.0b1
3.0.2
3.0.3
3.0.4
3.0.5
3.0a4
3.1
3.2
3.2.1
3.2.2
3.2.3
3.2.4
3.2.5
3.3
3.4
3.4.1
3.4.3
3.4.4
3.5
3.5b1
3.6
3.6.1
3.6.2
3.6.5
3.6.6
3.6.7
3.7
3.8
3.8.1
3.8.2
3.9
3.9.1
3.9.2
3.9.3
3.9.4
v3.*
v3.10.0-rc1
v3.9.2

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80205.json"