cbcvebase.
CVE-2020-15956
published 2020-08-04

CVE-2020-15956: ActiveMediaServer.exe in ACTi NVR3 Standard Server 3.0.12.42 allows remote unauthenticated attackers to trigger a buffer overflow and application termination…

PriorityP258high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EXPLOIT
EPSS
10.52%
95.2th percentile
ActiveMediaServer.exe in ACTi NVR3 Standard Server 3.0.12.42 allows remote unauthenticated attackers to trigger a buffer overflow and application termination via a malformed payload.

Affected

2 ranges
VendorProductVersion rangeFixed in
actinvr——
actinvr——

Detection & IOCsextracted from sources · hover to see the quote

path/media/Product/getProductInfo↗
path/Media/UserGroup/login↗
filenameActiveMediaServer.exe↗
bytes↗
\x00 * 760 (760 null bytes in HTTP Basic Auth credential field)
  • →Monitor HTTP GET requests to /Media/UserGroup/login containing an HTTP Basic Auth header with a large (≥760 byte) or null-byte-padded credential field, which is the trigger for the buffer overflow DoS against ActiveMediaServer.exe. ↗
  • →Attackers first probe /media/Product/getProductInfo (unauthenticated GET, HTTP 200) to fingerprint the ACTi NVR3 target before launching the DoS loop; alert on reconnaissance requests to this endpoint. ↗
  • →The exploit is sent by a remote unauthenticated attacker; no credentials are required to reach the vulnerable endpoint, so any external source hitting /Media/UserGroup/login with anomalous Auth headers should be treated as suspicious. ↗
  • ·The PoC loops continuously until interrupted (Ctrl-C / SIGINT), meaning the DoS is sustained rather than a single-shot attack; detection logic should account for high-frequency repeated requests to /Media/UserGroup/login from a single source IP. ↗
  • ·Both Standard (3.0.12.42) and Professional (V.2.3.04.07) versions of ACTi NVR3 Server are reported as affected; detections should cover both product variants. ↗

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
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