DEBIAN-CVE-2026-72818
- Source
- https://security-tracker.debian.org/tracker/CVE-2026-72818
- Import Source
- https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-72818.json
- JSON Data
- https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-72818
- Upstream
- Published
- 2026-08-20T22:18:05Z
- Modified
- 2026-09-14T17:03:52Z
- Severity
-
- 8.7 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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 CVSS Calculator
- Summary
- [none]
- Details
-
The URLS regular expression in nltk/tokenize/casual.py, compiled into TweetTokenizer.WORD_RE and applied by TweetTokenizer.tokenize, contains a naked-domain branch whose domain-label prefix [a-z0-9]+(?:[.-][a-z0-9]+)* is unbounded. Input consisting of many alternating label separators can be partitioned in exponentially many ways, and because the branch also requires a trailing top-level domain that such input never supplies, the engine explores those partitions before failing at each offset. A few kilobytes of input therefore consumes seconds to minutes of single-threaded CPU, and the HANG_RE substitution performed before matching does not collapse the pattern. TweetTokenizer is intended for tokenizing untrusted social-media text, so any service that applies it, or the module-level casual_tokenize, to submitted text can be stalled per request without authentication. Version 3.10.1 bounds the label repetition.
- References
Affected packages
Debian:12 / nltk
Package
- Name
- nltk
- Purl
- pkg:deb/debian/nltk?arch=source&distro=bookworm
Debian:13 / nltk
Package
- Name
- nltk
- Purl
- pkg:deb/debian/nltk?arch=source&distro=trixie
Debian:14 / nltk
Package
- Name
- nltk
- Purl
- pkg:deb/debian/nltk?arch=source&distro=forky