XXE in Openhab
CVE-2021-21266
openHAB is a vendor and technology agnostic open source automation software for your home. In openHAB before versions 2.5.12 and 3.0.1 the XML external entity (XXE) attack allows attackers in the same network as the openHAB instance to retrieve internal information like the content of files from the file system. Responses to SSDP requests can be especially malicious. All add-ons that use SAX or JAXB parsing of externally received XML are potentially subject to this kind of attack. In openHAB, the following add-ons are potentially impacted: AvmFritz, BoseSoundtouch, DenonMarantz, DLinkSmarthome, Enigma2, FmiWeather, FSInternetRadio, Gce, Homematic, HPPrinter, IHC, Insteon, Onkyo, Roku, SamsungTV, Sonos, Roku, Tellstick, TR064, UPnPControl, Vitotronic, Wemo, YamahaReceiver and XPath Tranformation. The vulnerabilities have been fixed in versions 2.5.12 and 3.0.1 by a more strict configuration of the used XML parser.
Vulnerability class: XXE (XML External Entity)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.011 (64.4th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 64th percentile — 64.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000
Affected products
- Openhab — versions 3.0.0
- Openhab Openhab-Addons — versions < 2.5.12, = 3.0.0
Weakness classification (CWE)
References
- github.com/openhab/openhab-addons/security/advisories/GHSA-r2hc-pmr7-4c9r (Patch, Third Party Advisory)
- dev.to/brianverm/configure-your-java-xml-parsers-to-prevent-xxe-213c (Third Party Advisory)
- www.contrastsecurity.com/security-influencers/xml-xxe-pitfalls-with-jaxb (Technical Description, Third Party Advisory)
- github.com/openhab/openhab-addons/commit/81935b0ab126e6d9aebd2f6c3fc67d82bb7e8b… (Patch, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-21266?
- CVE-2021-21266 is a medium-severity vulnerability in Openhab, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 6.4/10. Published 2021-02-01.
- How severe is CVE-2021-21266?
- Medium severity. CVSS v3 base score is 6.4 out of 10.