CVE-2021-33516

CVE-2021-33516 is a high-severity vulnerability in Gnome Gupnp with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

An issue was discovered in GUPnP before 1.0.7 and 1.1.x and 1.2.x before 1.2.5. It allows DNS rebinding. A remote web server can exploit this vulnerability to trick a victim's browser into triggering actions against local UPnP services implemented using this library. Depending on the affected service, this could be used for data exfiltration, data tempering, etc.

Frequently asked questions

What is CVE-2021-33516?
An issue was discovered in GUPnP before 1.0.7 and 1.1.x and 1.2.x before 1.2.5. It allows DNS rebinding. A remote web server can exploit this vulnerability to trick a victim's browser into triggering actions against local UPnP services implemented using this library. Depending on the affected service, this could be used for data exfiltration, data tempering, etc.
How severe is CVE-2021-33516?
CVE-2021-33516 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2021-33516 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33516?
CVE-2021-33516 affects Gnome Gupnp. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-33516?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-33516 published?
CVE-2021-33516 was published on 2021-05-24 and last updated on 2026-06-17.

References

Affected products (1)