Cyber Resilience

CVE-2019-16278

CriticalCISA KEVActive ExploitationEUVD ExploitedPublic PoC

Published: 14 October 2019

Published
14 October 2019
Modified
06 November 2025
KEV Added
07 November 2024
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.9439 100.0th percentile
Risk Priority 96 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2019-16278 is a critical-severity Path Traversal (CWE-22) vulnerability in Nazgul Nostromo Nhttpd. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 0.0% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and AC-6 (Least Privilege).

Deeper analysis

Nostromo nhttpd versions through 1.9.6 are affected by a directory traversal vulnerability in the http_verify function, tracked as CVE-2019-16278 and CWE-22. The issue resides in the HTTP request handling logic of this lightweight web server and enables an attacker to traverse the filesystem via malformed input.

The flaw can be exploited remotely by an unauthenticated attacker over the network using a crafted HTTP request. Successful exploitation grants arbitrary code execution with full impact on confidentiality, integrity, and availability, consistent with the CVSS 3.1 base score of 9.8.

Public exploit code demonstrating remote code execution has been published on PacketStorm and related repositories, confirming that working attacks against unpatched instances are readily available. No official vendor advisory or patch information is referenced in the available sources.

EU & UK References

Vulnerability details

Directory Traversal in the function http_verify in nostromo nhttpd through 1.9.6 allows an attacker to achieve remote code execution via a crafted HTTP request.

CWE(s)
KEV Date Added
07 November 2024

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

nazgul
nostromo nhttpd
≤ 1.9.7

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly blocks the crafted HTTP request input containing directory traversal sequences before http_verify processes it.

prevent

Boundary filtering or proxy rules can inspect and drop malicious HTTP requests targeting the vulnerable nhttpd endpoint.

prevent

Running nhttpd under minimal privileges limits the scope of arbitrary code execution that the traversal enables.

References