---
id: "CVE-2025-71436"
kind: "vulnerability"
aliases: ["CVE-2025-71436"]
title: "Raptor RDF library: heap overflow from long language tags in RDF documents"
severity: "high"
cvss: 7.1
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["c", "libraries", "package", "raptor", "rdf", "semantic-web"]
not_affected_if: ["no-rdf-parsing", "trusted-input-only"]
published_at: "2026-10-20T16:16:59+00:00"
first_seen_at: "2026-10-23T21:57:20+00:00"
updated_at: "2026-10-25T03:34:41+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-71436", "first_seen_at": "2026-10-23T21:57:20+00:00"}]
---

# Raptor RDF library: heap overflow from long language tags in RDF documents

Raptor, a C library for parsing RDF data, truncates language tag lengths to an unsigned char, so Turtle, TriG, N-Triples or N-Quads input with language tags of 256 bytes or more corrupts heap memory. An attacker who supplies such a document can crash the parsing application and possibly run code.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed Raptor version with `raptor2-config --version` or the package manager, and look for versions `2.0.15` and `2.0.16`.
- Search application dependencies and bundled libraries for `raptor2` or `libraptor`.
- unknown

## Fix

- Move Raptor past `2.0.16` once a fixed release is available; the sources do not name the fixed version.
- Until patched, reject or pre-filter RDF input with language tags of 256 bytes or longer.

## Timeline

- 2026-10-23T21:57:20+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2025-71436

## From the sources

Raptor RDF Syntax Library from 2.0.15 through 2.0.16 contains a heap-based buffer overflow vulnerability in raptor_new_term_from_counted_literal() caused by truncating language tag length to an unsigned char. Attackers can supply Turtle, TriG, N-Triples or N-Quads documents with language tags of 256 bytes or longer to corrupt heap memory, crash applications, and possibly execute code.

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