CVE intelligence and bounded remediation
CVE-2023-45139 — fontTools is a library for manipulating fonts, written in Python
fontTools is a library for manipulating fonts, written in Python. The subsetting module has a XML External Entity Injection (XXE) vulnerability which allows an attacker to resolve arbitrary entities when a candidate font (OT-SVG fonts), which contains a SVG table, is parsed. This allows attackers to include arbitrary files from the filesystem fontTools is running on or make web requests from the host system. This vulnerability has been patched in version 4.43.0.
- Severity
- High
- CVSS
- 7.5 (3.1)
- Published
- 2024-01-10
- CISA KEV
- Not currently listed
- Ecosystem
- python/pypi
- Weaknesses
- CWE-611
Affected products
- fonttools / fonttools
Matched remediation archetype
XML external entity and unsafe XML processing
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Inventory XML parsers used by APIs, file imports, office or image formats, identity protocols, feeds, and background jobs.
- Determine whether document type declarations, external entities, XInclude, schemas, or network resolvers are enabled.
- Map parser filesystem and network access and the sensitivity of documents it processes.
Remediate safely
- Configure each parser to reject document type declarations and disable external entity, XInclude, and network resolution features.
- Prefer a data format or hardened parser that does not support external resolution, and apply input size and depth limits.
- Update affected XML libraries and centralize secure parser construction so callers cannot silently override it.
Authoritative sources
Complete CVE record and remediation plan
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