CVE-2026-49140

MEDIUM EPSS 18.4%
Published Jun 1, 20261mo ago · Modified Jun 17, 20262w ago
5.3 CVSS 4.0
Medium
Find Similar
Published Jun 1, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago

Description

Nanobot prior to version 0.2.1 contains a denial of service vulnerability in the Matrix channel media download handler that allows authenticated room members to exhaust process memory and bandwidth by sending media events with missing or invalid size metadata. Attackers can send multiple concurrent Matrix media events with omitted or invalid declared sizes to trigger simultaneous large media downloads that fully materialize response bodies before post-download rejection, consuming process resources until service degradation occurs.

CVSS Details

Base Score
5.3
Exploitability
—
Impact
—
Vector string
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
18.4% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-770

References 4

  • github.com https://github.com/HKUDS/nanobot/commit/1d4000560dfff1acb83f5c5ca8ef3ab1f092bd14
  • github.com https://github.com/HKUDS/nanobot/pull/4106
  • github.com https://github.com/HKUDS/nanobot/releases/tag/v0.2.1
  • vulncheck.com https://www.vulncheck.com/advisories/nanobot-denial-of-service-via-matrix-media-download-handler

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.