CVE-2026-2581
CWE-770Published: March 12, 2026· Updated: Mar 18, 2026
Official Description
This is an uncontrolled resource consumption vulnerability (CWE-400) that can lead to Denial of Service (DoS).
In vulnerable Undici versions, when interceptors.deduplicate() is enabled, response data for deduplicated requests could be accumulated in memory for downstream handlers. An attacker-controlled or untrusted upstream endpoint can exploit this with large/chunked responses and concurrent identical requests, causing high memory usage and potential OOM process termination.
Impacted users are applications that use Undici’s deduplication interceptor against endpoints that may produce large or long-lived response bodies.
PatchesThe issue has been patched by changing deduplication behavior to stream response chunks to downstream handlers as they arrive (instead of full-body accumulation), and by preventing late deduplication when body streaming has already started.
Users should upgrade to the first official Undici (and Node.js, where applicable) releases that include this patch.
Technical Analysis
CVE-2026-2581 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 5.9.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (3)
Quick Facts
Related CVEs (CWE-770)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-2581 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts