CVE-2017-7921: Hikvision Multiple Products Critical Vulnerability

What is CVE-2017-7921?

An Improper Authentication issue was discovered in Hikvision DS-2CD2xx2F-I Series V5.2.0 build 140721 to V5.4.0 build 160530, DS-2CD2xx0F-I Series V5.2.0 build 140721 to V5.4.0 Build 160401, DS-2CD2xx2FWD Series V5.3.1 build 150410 to V5.4.4 Build 161125, DS-2CD4x2xFWD Series V5.2.0 build 140721 to V5.4.0 Build 160414, DS-2CD4xx5 Series V5.2.0 build 140721 to V5.4.0 Build 160421, DS-2DFx Series V5.2.0 build 140805 to V5.4.5 Build 160928, and DS-2CD63xx Series V5.0.9 build 140305 to V5.3.5 Build 160106 devices. The improper authentication vulnerability occurs when an application does not adequately or correctly authenticate users. This may allow a malicious user to escalate his or her privileges on the system and gain access to sensitive information.

Technical Analysis

Weakness Classification

This vulnerability is classified as CWE-287 — Improper Authentication. The authentication mechanism can be bypassed or is implemented incorrectly, allowing unauthorized access.

Attack Vector Breakdown

• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: None
• Scope: Unchanged
• Confidentiality: High
• Integrity: High
• Availability: High

Impact Analysis

This vulnerability is exploitable over the network, meaning any system reachable via the internet or internal network is potentially at risk without physical access. The attack complexity is low, requires no special privileges, and needs no user interaction — making it straightforward to exploit at scale. Successful exploitation can result in full confidentiality breach (complete data disclosure), complete integrity compromise (data modification or code execution), total availability loss (denial of service). The authentication mechanism can be bypassed or is implemented incorrectly, allowing unauthorized access.

Exploitation Probability (EPSS): 94.2% chance of exploitation in the next 30 days (100th percentile). This places the vulnerability in the highest risk tier — immediate action is critical.

Exploit Availability

Public exploit code or proof-of-concept is available for CVE-2017-7921. This significantly increases the risk of exploitation, as attackers can use or adapt existing exploit code rather than developing their own. A public exploit reference has been identified. Organizations should treat this as an urgent patching priority.

Is CVE-2017-7921 being exploited?

Yes. CVE-2017-7921 is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, restricted to CVEs with confirmed active exploitation in the wild. CISA added this vulnerability on 2026-03-05. Inclusion in KEV triggers the patching mandate under BOD 22-01 for U.S. federal civilian agencies, with a remediation deadline of 2026-03-26. Additionally, public exploit code is available, which lowers the barrier for attackers.

How to fix CVE-2017-7921

Apply the security update issued by Hikvision for Multiple Products. If an immediate patch is not possible, consult the vendor advisory for mitigation guidance, restrict network exposure of the affected service, and monitor logs for indicators of exploitation. CISA's Known Exploited Vulnerabilities catalog requires U.S. federal agencies to remediate this vulnerability by the due date shown below under Binding Operational Directive 22-01. Private organizations should treat KEV entries as priority-one patches because active exploitation has been confirmed in the wild.

Related Vulnerabilities

Other actively exploited vulnerabilities affecting Multiple Products or sharing the same weakness (CWE-287):

• CVE-2025-43510 (High 7.8) [same product] — A memory corruption issue was addressed with improved lock state checking…
• CVE-2025-43520 (Medium 5.5) [same product] — A memory corruption issue was addressed with improved memory handling. This…
• CVE-2025-31277 (High 8.8) [same product] — The issue was addressed with improved memory handling. This issue is fixed in…
• CVE-2021-22681 (Critical 9.8) [same product] — Rockwell Automation Studio 5000 Logix Designer Versions 21 and later, and…
• CVE-2023-43000 (High 8.8) [same product] — A use-after-free issue was addressed with improved memory management. This…

Frequently asked questions

Is CVE-2017-7921 critical?

CVE-2017-7921 has a CVSS 3.1 base score of 9.8 — Critical severity. It should be treated as a priority patch, especially given the active exploitation confirmed by CISA. The availability of public exploit code further increases the urgency.

Is CVE-2017-7921 being actively exploited?

Yes — CISA added CVE-2017-7921 to the Known Exploited Vulnerabilities catalog on 2026-03-05. Inclusion in KEV means CISA has confirmed in-the-wild exploitation. Public exploit code has also been identified, making exploitation accessible to a broader range of threat actors.

How do I patch CVE-2017-7921?

Apply the security update from Hikvision for Multiple Products. Federal agencies must remediate by 2026-03-26 under BOD 22-01.

What type of vulnerability is CVE-2017-7921?

CVE-2017-7921 is classified under CWE-287 (Improper Authentication). The authentication mechanism can be bypassed or is implemented incorrectly, allowing unauthorized access.

What is the CVSS score for CVE-2017-7921?

CVE-2017-7921 has a CVSS 3.1 base score of 9.8, classifying it as Critical severity. The attack vector is Network, attack complexity is Low, and no privileges are required.