4.8
MEDIUM CVSS 4.0
CVE-2026-42934
NGINX ngx_http_charset_module vulnerability
Description

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_charset_module module. When charset, source_charset, and charset_map and proxy_pass with disabled buffering ("off") directives are configured, unauthenticated attackers can send requests that with conditions beyond the attackers' control to cause a heap buffer over-read in the NGINX worker process, leading to limited disclosure of memory or a restart.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

INFO

Published Date :

May 13, 2026, 4:16 p.m.

Last Modified :

May 13, 2026, 4:27 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-42934 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 F5 nginx_plus
2 F5 nginx_open_source
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM 9dacffd4-cb11-413f-8451-fbbfd4ddc0ab
CVSS 3.1 MEDIUM [email protected]
CVSS 3.1 MEDIUM MITRE-CVE
CVSS 4.0 MEDIUM 9dacffd4-cb11-413f-8451-fbbfd4ddc0ab
CVSS 4.0 MEDIUM [email protected]
Public PoC/Exploit Available at Github

CVE-2026-42934 has a 13 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-42934.

URL Resource
https://my.f5.com/manage/s/article/K000161028
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-42934 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-42934 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

CVE-2026-42945 turns a 17-year-old NGINX rewrite bug into remote code execution — even with ASLR on, by chaining the heap overflow with live worker memory read through a common file-read flaw.

Python

Updated: 1 week, 2 days ago
1 stars 0 fork 0 watcher
Born at : May 25, 2026, 12:06 p.m. This repo has been linked 4 different CVEs too.

None

Updated: 1 week, 4 days ago
0 stars 0 fork 0 watcher
Born at : May 23, 2026, 3:21 p.m. This repo has been linked 4 different CVEs too.

PoC for CVE-2026-42945 (nginx Rift) — heap buffer overflow in ngx_http_rewrite_module. Includes detect/probe/exploit modes, dual-fixture Docker lab, empirical address discovery, OOB-verified offset sweep. Original disclosure by depthfirst.

buffer-overflow cve cve-2026-42945 exploit-development heap-overflow nginx poc rce security-research nginx-exploit

Python Shell

Updated: 1 week, 5 days ago
0 stars 0 fork 0 watcher
Born at : May 22, 2026, 6:23 p.m. This repo has been linked 4 different CVEs too.

Private Nginx Rift ASLR lab, exploit chain, and demo recordings

Python GDB Shell

Updated: 2 weeks, 1 day ago
0 stars 0 fork 0 watcher
Born at : May 19, 2026, 6:29 p.m. This repo has been linked 4 different CVEs too.

nginx CVE scanner + RCE exploit framework (CVE-2026-42945 + 16 others)

Python

Updated: 2 weeks, 2 days ago
3 stars 3 fork 3 watcher
Born at : May 16, 2026, 2:25 p.m. This repo has been linked 53 different CVEs too.

None

Shell

Updated: 2 weeks, 4 days ago
0 stars 0 fork 0 watcher
Born at : May 16, 2026, 12:13 p.m. This repo has been linked 4 different CVEs too.

Trigger-aware web server CVE audit for nginx and Apache. Goes beyond version matching by checking whether the vulnerable code path is actually reachable in your configuration. Classifies findings as Active / Latent / Unverified. Single-file Python 3.5+, no dependencies.

Python

Updated: 2 weeks, 4 days ago
0 stars 0 fork 0 watcher
Born at : May 16, 2026, 9:06 a.m. This repo has been linked 4 different CVEs too.

None

Python Shell

Updated: 2 weeks, 4 days ago
1 stars 0 fork 0 watcher
Born at : May 15, 2026, 9:57 a.m. This repo has been linked 4 different CVEs too.

Private Nginx Rift ASLR lab, exploit chain, and demo recordings

Python GDB Shell

Updated: 2 weeks, 1 day ago
0 stars 1 fork 1 watcher
Born at : May 15, 2026, 12:12 a.m. This repo has been linked 4 different CVEs too.

None

Python Shell

Updated: 2 weeks, 3 days ago
12 stars 7 fork 7 watcher
Born at : May 14, 2026, 6:12 a.m. This repo has been linked 4 different CVEs too.

exploit for CVE-2026-42945

Shell Python

Updated: 2 weeks, 1 day ago
710 stars 121 fork 121 watcher
Born at : May 12, 2026, 11:05 p.m. This repo has been linked 4 different CVEs too.

WNMP One‑Click Stack | WebDAV · Nginx · PHP · MariaDB · Kernel Tuning

Shell

Updated: 2 weeks, 4 days ago
26 stars 4 fork 4 watcher
Born at : Dec. 7, 2025, 11:39 p.m. This repo has been linked 6 different CVEs too.

使用Google Gemini API,对hacker news Top100文章总结摘要并翻译成体中文,每日自动更新。

ai gemini hacker-news hackernews summarizer

Ruby Shell Python

Updated: 2 weeks, 5 days ago
17 stars 4 fork 4 watcher
Born at : March 19, 2025, 11:57 a.m. This repo has been linked 4 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-42934 vulnerability anywhere in the article.

  • TheCyberThrone
CVE-2026-42945 — NGINX Heap Buffer Overflow RCE

CVE: CVE-2026-42945CVSS: 9.2 — CriticalVendor: NGINX / F5Affected Versions: 0.6.27 through 1.30.0Vulnerability Type: Heap Buffer OverflowImpact: Unauthenticated Remote Code ExecutionPoC Available: Yes ... Read more

Published Date: May 17, 2026 (2 weeks, 3 days ago)
  • Daily CyberSecurity
Nginx Releases Critical Update: Six Vulnerabilities Patched in New Stable Version

The web infrastructure world received a major wake-up call today as nginx-1.30.1 was released to address a suite of six security vulnerabilities. These flaws range from high-severity arbitrary code ex ... Read more

Published Date: May 14, 2026 (2 weeks, 6 days ago)
  • CybersecurityNews
Critical 18-Year-Old NGINX Vulnerability Enables Remote Code Execution Attacks

A critical heap buffer overflow vulnerability has been discovered in the source code of NGINX, present since 2008. This vulnerability has been publicly disclosed, along with a working proof-of-concept ... Read more

Published Date: May 14, 2026 (2 weeks, 6 days ago)
  • The Hacker News
18-Year-Old NGINX Rewrite Module Flaw Enables Unauthenticated RCE

Cybersecurity researchers have disclosed multiple security vulnerabilities impacting NGINX Plus and NGINX Open, including a critical flaw that remained undetected for 18 years. The vulnerability, disc ... Read more

Published Date: May 14, 2026 (2 weeks, 6 days ago)

The following table lists the changes that have been made to the CVE-2026-42934 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    May. 13, 2026

    Action Type Old Value New Value
    Added Description NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_charset_module module. When charset, source_charset, and charset_map and proxy_pass with disabled buffering ("off") directives are configured, unauthenticated attackers can send requests that with conditions beyond the attackers' control to cause a heap buffer over-read in the NGINX worker process, leading to limited disclosure of memory or a restart.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/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
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
    Added CWE CWE-125
    Added Reference https://my.f5.com/manage/s/article/K000161028
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.