CVE-2026-81723

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.28% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 20.3% of scored records. A rank, not a probability.

NVD base score

6.3 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/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

NVD analysis status

Awaiting Analysis. NVD last modified this record on 2026-09-24.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-08-27 14:51Z2 MO AGO

Last updated

2026-08-31 18:12Z1 MO AGO

Reserved

2026-08-27

Assigning CNA

VulnCheck

Record state

PUBLISHED

Severity

Medium (CVSS 6.3)

CNA CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

Weaknesses

• CWE-400Uncontrolled Resource ConsumptionClass
• CWE-776Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion')Base

Data version

5.2

Document digest

4c87ec0ce9d176b536e6ef642b0aca7c236785d8a872df1f6eb811b7b7d1c4b4

• github.comGitHub Security Advisory (GHSA-vp2x-qp44-57v7)https://github.com/nltk/nltk/security/advisories/GHSA-vp2x-qp44-57v7vendor-advisory
• www.vulncheck.comVulnCheck Advisory: NLTK before 3.10.3 Quadratic CPU Exhaustion via XMLCorpusViewhttps://www.vulncheck.com/advisories/nltk-before-3.10.3-quadratic-cpu-exhaustion-via-xmlcorpusviewthird-party-advisory