CVE-2026-81724
Last modified
CVE-2026-81724 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. NLTK before 3.10.3 contains an uncontrolled recursion vulnerability in nltk.featstruct.FeatStructReader that allows unauthenticated attackers to cause a denial of service by supplying deeply nested feature-structure input. Attackers can craft trivial payloads with nested brackets that exceed Python's recursion limit and raise an unhandled RecursionError, crashing applications that parse user-supplied feature structures or feature grammars.. EPSS estimates a 0.26% chance of exploitation in the next 30 days.
Description
NLTK before 3.10.3 contains an uncontrolled recursion vulnerability in nltk.featstruct.FeatStructReader that allows unauthenticated attackers to cause a denial of service by supplying deeply nested feature-structure input. Attackers can craft trivial payloads with nested brackets that exceed Python's recursion limit and raise an unhandled RecursionError, crashing applications that parse user-supplied feature structures or feature grammars.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Nltk | Nltk | < 3.10.3 |
References
- https://github.com/nltk/nltk/security/advisories/GHSA-cw6x-m8jw-qmrhExploit, Vendor Advisory
- https://github.com/nltk/nltk/security/advisories/GHSA-cw6x-m8jw-qmrhExploit, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-81724?
How severe is CVE-2026-81724?
How do I fix CVE-2026-81724?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-81719openssl_encrypt before 1.4.9 executes untrusted third-party …7.8
- CVE-2026-8172The Simple Basic Contact Form WordPress plugin through 20250…7.1
- CVE-2026-81720openssl_encrypt before 1.4.9 fails to validate the memory_co…6.2
- CVE-2026-81721openssl_encrypt before 1.4.9 fails to validate KDF cost para…7.5
- CVE-2026-81722nltk PorterStemmer in versions <= 3.10.2 (fixed in 3.10.3) c…7.5
- CVE-2026-81723NLTK versions before 3.10.3 contain a quadratic CPU exhausti…3.7
- CVE-2026-81725NLTK before 3.10.3 contains a regular expression denial of s…3.7
- CVE-2026-81726NLTK through 3.10.3 contains a path traversal vulnerability …7
- CVE-2026-81727NLTK versions before 3.10.3 contain a filesystem containment…7.1
- CVE-2026-81728Dolibarr before 24.0.0 contains a SQL injection in its CSV a…8.1
- CVE-2026-81729Dolibarr before 23.0.4 authorizes REST API document deletion…6.5
- CVE-2026-8173The web GUI of affected Murrelektronik Xelity switches logs …5.3
Are you affected by CVE-2026-81724?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST