Cyber Resilience

CVE-2021-21266

Medium

Published: 01 February 2021

Published
01 February 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 6.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
EPSS Score 0.0036 58.6th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-21266 is a medium-severity Improper Restriction of XML External Entity Reference (CWE-611) vulnerability in Openhab Openhab. Its CVSS base score is 6.4 (Medium).

Operationally, ranked in the top 41.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

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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.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

openhab
openhab
3.0.0 · ≤ 2.5.12

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-611

Penetration testing includes XML external entity payloads, detecting XXE vulnerabilities and enabling their mitigation.

addresses: CWE-611

Identifies XML external entity processing via monitoring of unusual file/network access or resource usage.

References