CVE-2026-62388: nltk
CVSS: 8.7v4.0HighAnalyzed
AliasesGHSA-p3m8-78j2-g5p3PYSEC-2026-3722UBUNTU-CVE-2026-62388DEBIAN-CVE-2026-62388
Published 22-08-2026Last modified 29-08-2026
Vulnerability summary
CVE-2026-62388 is a high (CVSS 8.7) vulnerability in nltk. EPSS estimates a 0.51% chance of exploitation in the next 30 days, higher than 42.4% of scored vulnerabilities. 1 public exploit is recorded.
CVSS score
8.7/10
010
High · v4.0 (CVE.org)EPSS score
0.51%
0%100%
Low · +0.06 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github
Advisory lineage
Upstream 0 · Downstream 1Timeline
- 22-08-2026PublishedVulnerability first disclosed.
- 29-08-2026Last modifiedVulnerability information updated.
Description
NLTK versions before 3.10.0 default to ENFORCE=False in pathsec.py, causing all security validation functions to emit warnings instead of raising exceptions. Attackers can bypass path traversal and pickle deserialization protections by exploiting the disabled security controls that are only active when manually enabled.
CVSS metrics
8 scores · 5 sources · 2 versionsHigh 8.7Preferred score · CVE.org (CNA)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:NSourcesAll 5 agree
- OSV · PypiEcosystem advisory · calculated8.7HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/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
- OSV · UbuntuEcosystem advisory · calculated8.7HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
- OSV · DebianEcosystem advisory · calculated8.7HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/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
- NVDNIST8.7HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/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
High 7.5Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:NSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- NVDNIST7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS trend
Probability
0.51%
Chance of exploitation in the next 30 days
Percentile
42%
Versus all other CVEs
30-day change
+0.06 pp
From 0.46% on 19-09-2026
19-09-202619-10-2026
EPSS score0.51%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundNltk
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Debian1 product
- nltkAll versions (No fix recorded) | < 3.10.0-1
Nltk1 product
- nltk< 3.10.0
PyPI1 product
- nltk< 3.10.0
Ubuntu1 product
- nltkAll versions (No fix recorded)
4 vendors · 4 products
References
15 links- github.com/nltk/nltk/security/advisories/GHSA-p3m8-78j2-g5p3Vendor AdvisoryWEBEVIDENCEExploitMitigation
- www.vulncheck.com/advisories/nltk-before-insecure-default-configuration-pathsecThird Party AdvisoryWEBAdvisoryREPORT
- github.com/nltk/nltkPACKAGE
