CVE-2026-80205

NLTK before 3.10.0 ReDoS via Text.findall() unvalidated regex

HIGH
7.5
CVSS Score
Published: August 26, 2026 at 10:28 AM UTC
Updated: September 3, 2026 at 05:15 AM UTC
1 product affected across 1 vendorNltk

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Severity
HIGH7.5
Exploit prediction
EPSS 0.7%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 3.10.0
Vendor states this is fixed in 3.10.0 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHVulnCheck
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-1333

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