CVE-2026-126295nltk path traversal
CVE-2026-126295 is a path traversal in nltk, rated high (7.0 on CVSS 4.0).
Why this priority: High severity, with no exploitation signal yet.
Published · Updated · NVD status: Awaiting Analysis
What it is
A file name from the request can climb out of the intended folder with sequences like ../, reaching files the service never meant to expose.
How it is reached
An attacker can exploit it by someone who can already run code or sign in on the machine, without an account, and nobody has to click anything.
What an attacker gains
A successful attack can read the data it protects. In practice, this kind of flaw lets an attacker read or write files outside the folders the service meant to expose.
Is it being exploited?
There is no public report of exploitation yet. EPSS estimates a 0.20% chance of exploitation activity in the next 30 days, higher than 10% of scored CVEs.
What to do
- Upgrade nltk to 3.10.4 or later.
- Limit who can run code or sign in on the hosts that run it.
Description from NVD
NLTK from 3.10.0 before 3.10.4 contains an arbitrary file read vulnerability in BllipParser that allows attackers to open files outside NLTK data roots by supplying unvalidated model paths. Attackers controlling parser_model, reranker_features, reranker_weights, or from_unified_model_dir() input can make the bllipparser C extension read sensitive files or block on FIFOs and devices.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- File storage the service can read or write. The flaw sits between the application and the file system it can reach.
Trust boundaries in play
- Host boundary. The attacker needs a foothold on the machine first; the flaw turns a small foothold into a bigger one.
- Between the application and the file system it can reach. An attacker who crosses it can read or write files outside the folders the service meant to expose.
Questions to answer about your own systems
- Where does nltk run in your systems, and at which version?
- Which of those hosts also run code or users you do not fully trust?
- What can it reach once compromised: which data stores, secrets and services?
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.