Skip to main content

CWE-158

Improper Neutralization of Null Byte or NUL Character

23 CVEs Avg CVSS 6.5 MITRE
4
CRITICAL
6
HIGH
8
MEDIUM
5
LOW
2
POC
1
KEV

Monthly

CVE-2026-76354 Aug 19, 21:34 HIGH PATCH This Week

Search Head Clustering bundle replication in Splunk Enterprise fails to validate bundle filenames or neutralize NUL bytes before constructing file system paths on non-captain cluster members, allowing any authenticated low-privileged user to delete or temporarily overwrite files accessible to the Splunk service account via a crafted REST API request. Affected are Splunk Enterprise versions below 10.4.2, 10.2.6, 10.0.9, and 9.4.14 running in SHC deployments - standalone instances are not in scope. No public exploit code has been identified at time of analysis and this CVE is not listed in CISA KEV; however, vendor patch is available via advisory SVD-2026-0801 and the low privilege barrier makes this a credible insider or stolen-credential threat in SOC environments.

Splunk Information Disclosure Splunk Enterprise
NVD
CVSS 3.1
8.1
EPSS
0.2%
CVE-2026-47778 Jun 26, 17:27 MEDIUM PATCH This Month

Certificate SAN validation in Envoy Proxy is bypassed when an attacker-controlled upstream serves a TLS certificate containing an embedded NUL byte in the dNSName Subject Alternative Name field. Envoy versions prior to 1.35.11, 1.36.7, 1.37.3, and 1.38.1 are affected, allowing an attacker who controls or can impersonate an upstream TLS endpoint to pass Envoy's configured SAN match check with a fraudulent certificate and intercept proxied traffic. No public exploit code has been identified at time of analysis, and this vulnerability is not listed in the CISA KEV catalog.

Information Disclosure Envoy Red Hat Suse
NVD GitHub VulDB
CVSS 3.1
4.4
EPSS
0.2%
CVE-2026-41256 May 11, 17:18 MEDIUM PATCH This Month

Jq 1.8.1 and earlier truncate filter files at the first embedded NUL byte when loaded with -f, causing only the prefix before the NUL to execute. A crafted filter file containing a NUL byte and arbitrary suffix allows an attacker to inject malicious code that compiles and runs silently, bypassing intended filter logic and potentially modifying JSON output in undetected ways. This represents a post-CVE-2026-33948 regression on the compilation path.

Information Disclosure Red Hat
NVD GitHub VulDB
CVSS 3.1
5.5
EPSS
0.0%
CVE-2026-43861 May 04, 05:52 LOW PATCH Monitor

mutt before version 2.3.2 fails to validate null bytes during URL percent-decoding, allowing remote attackers to inject embedded null characters into decoded URLs, potentially causing information disclosure through truncation of validation checks or bypassing of security filters that rely on string length.

Information Disclosure Mutt
NVD GitHub VulDB
CVSS 3.1
3.7
EPSS
0.0%
CVE-2026-43859 May 04, 05:41 LOW PATCH Monitor

Mutt before 2.3.2 uses an unsafe string copy function (strfcpy) instead of memcpy when handling MD5 digest data in IMAP CRAM authentication, allowing attackers to potentially forge IMAP credentials by triggering buffer manipulation during the authentication handshake. The vulnerability requires manual connection attempt to a malicious IMAP server and affects network IMAP authentication flows, though the low CVSS score (3.7) reflects high attack complexity and integrity impact only.

Information Disclosure Mutt
NVD GitHub VulDB
CVSS 3.1
3.7
EPSS
0.0%
CVE-2026-23863 May 01, 16:16 MEDIUM PATCH This Month

WhatsApp for Windows prior to v2.3000.1032164386.258709 permits attachment spoofing via maliciously formatted documents with embedded NUL bytes in filenames, causing the application to display files as benign types while executing them as executables upon opening. The vulnerability requires user interaction to open a crafted attachment delivered over the network, enabling an attacker to achieve code execution with the privileges of the WhatsApp process. No public exploit code or active exploitation has been confirmed at time of analysis.

Microsoft Information Disclosure
NVD
CVSS 3.1
6.5
EPSS
0.0%
CVE-2026-33191 Mar 18, 20:11 Go HIGH PATCH This Week

Null byte injection in the UDM's Nudm_SubscriberDataManagement API allows unauthenticated remote attackers to crash the service by embedding URL-encoded %00 characters in the supi parameter, triggering unhandled parsing errors and denial of service. The vulnerability stems from improper input validation that permits control characters to reach Go's URL parser, which rejects them with a 500 error instead of sanitizing the input upstream. A patch is available.

Denial Of Service Suse
NVD GitHub VulDB
CVSS 3.1
8.6
EPSS
0.2%
CVE-2026-4359 Mar 17, 19:42 LOW PATCH Monitor

Crash-inducing denial-of-service in the MongoDB C Driver (all versions before 2.2.3) allows a network-privileged adversary - either a compromised third-party cloud server the application trusts or a man-in-the-middle attacker on the network path - to crash the consuming application by delivering a malformed HTTP response. The vulnerability carries a CVSS 4.0 score of 2.0 due to high attack complexity, prerequisite network positioning, and impact limited strictly to low availability on the vulnerable system. No public exploit code exists and EPSS probability sits at 0.03% (8th percentile), indicating negligible observed exploitation activity at time of analysis.

Denial Of Service Mongodb C Driver
NVD VulDB
CVSS 4.0
2.0
EPSS
0.0%
CVE-2026-28540 Mar 05, 08:15 MEDIUM This Month

Out-of-bounds character read vulnerability in Bluetooth. Impact: Successful exploitation of this vulnerability may affect service confidentiality. [CVSS 4.0 MEDIUM]

Buffer Overflow Harmonyos
NVD
CVSS 3.1
4.0
EPSS
0.0%
CVE-2025-66263 Nov 26, 01:16 HIGH POC This Week

Unauthenticated Arbitrary File Read via Null Byte Injection in DB Electronica Telecomunicazioni S.p.A. Rated high severity (CVSS 8.9), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.

PHP Authentication Bypass Mozart Next 3000 Firmware Mozart Next 3500 Firmware Mozart Next 50 Firmware +19
NVD
CVSS 4.0
8.9
EPSS
0.1%
EPSS 0% CVSS 8.1
HIGH PATCH This Week

Search Head Clustering bundle replication in Splunk Enterprise fails to validate bundle filenames or neutralize NUL bytes before constructing file system paths on non-captain cluster members, allowing any authenticated low-privileged user to delete or temporarily overwrite files accessible to the Splunk service account via a crafted REST API request. Affected are Splunk Enterprise versions below 10.4.2, 10.2.6, 10.0.9, and 9.4.14 running in SHC deployments - standalone instances are not in scope. No public exploit code has been identified at time of analysis and this CVE is not listed in CISA KEV; however, vendor patch is available via advisory SVD-2026-0801 and the low privilege barrier makes this a credible insider or stolen-credential threat in SOC environments.

Splunk Information Disclosure Splunk Enterprise
NVD
EPSS 0% CVSS 4.4
MEDIUM PATCH This Month

Certificate SAN validation in Envoy Proxy is bypassed when an attacker-controlled upstream serves a TLS certificate containing an embedded NUL byte in the dNSName Subject Alternative Name field. Envoy versions prior to 1.35.11, 1.36.7, 1.37.3, and 1.38.1 are affected, allowing an attacker who controls or can impersonate an upstream TLS endpoint to pass Envoy's configured SAN match check with a fraudulent certificate and intercept proxied traffic. No public exploit code has been identified at time of analysis, and this vulnerability is not listed in the CISA KEV catalog.

Information Disclosure Envoy Red Hat +1
NVD GitHub VulDB
EPSS 0% CVSS 5.5
MEDIUM PATCH This Month

Jq 1.8.1 and earlier truncate filter files at the first embedded NUL byte when loaded with -f, causing only the prefix before the NUL to execute. A crafted filter file containing a NUL byte and arbitrary suffix allows an attacker to inject malicious code that compiles and runs silently, bypassing intended filter logic and potentially modifying JSON output in undetected ways. This represents a post-CVE-2026-33948 regression on the compilation path.

Information Disclosure Red Hat
NVD GitHub VulDB
EPSS 0% CVSS 3.7
LOW PATCH Monitor

mutt before version 2.3.2 fails to validate null bytes during URL percent-decoding, allowing remote attackers to inject embedded null characters into decoded URLs, potentially causing information disclosure through truncation of validation checks or bypassing of security filters that rely on string length.

Information Disclosure Mutt
NVD GitHub VulDB
EPSS 0% CVSS 3.7
LOW PATCH Monitor

Mutt before 2.3.2 uses an unsafe string copy function (strfcpy) instead of memcpy when handling MD5 digest data in IMAP CRAM authentication, allowing attackers to potentially forge IMAP credentials by triggering buffer manipulation during the authentication handshake. The vulnerability requires manual connection attempt to a malicious IMAP server and affects network IMAP authentication flows, though the low CVSS score (3.7) reflects high attack complexity and integrity impact only.

Information Disclosure Mutt
NVD GitHub VulDB
EPSS 0% CVSS 6.5
MEDIUM PATCH This Month

WhatsApp for Windows prior to v2.3000.1032164386.258709 permits attachment spoofing via maliciously formatted documents with embedded NUL bytes in filenames, causing the application to display files as benign types while executing them as executables upon opening. The vulnerability requires user interaction to open a crafted attachment delivered over the network, enabling an attacker to achieve code execution with the privileges of the WhatsApp process. No public exploit code or active exploitation has been confirmed at time of analysis.

Microsoft Information Disclosure
NVD
EPSS 0% CVSS 8.6
HIGH PATCH This Week

Null byte injection in the UDM's Nudm_SubscriberDataManagement API allows unauthenticated remote attackers to crash the service by embedding URL-encoded %00 characters in the supi parameter, triggering unhandled parsing errors and denial of service. The vulnerability stems from improper input validation that permits control characters to reach Go's URL parser, which rejects them with a 500 error instead of sanitizing the input upstream. A patch is available.

Denial Of Service Suse
NVD GitHub VulDB
EPSS 0% CVSS 2.0
LOW PATCH Monitor

Crash-inducing denial-of-service in the MongoDB C Driver (all versions before 2.2.3) allows a network-privileged adversary - either a compromised third-party cloud server the application trusts or a man-in-the-middle attacker on the network path - to crash the consuming application by delivering a malformed HTTP response. The vulnerability carries a CVSS 4.0 score of 2.0 due to high attack complexity, prerequisite network positioning, and impact limited strictly to low availability on the vulnerable system. No public exploit code exists and EPSS probability sits at 0.03% (8th percentile), indicating negligible observed exploitation activity at time of analysis.

Denial Of Service Mongodb C Driver
NVD VulDB
EPSS 0% CVSS 4.0
MEDIUM This Month

Out-of-bounds character read vulnerability in Bluetooth. Impact: Successful exploitation of this vulnerability may affect service confidentiality. [CVSS 4.0 MEDIUM]

Buffer Overflow Harmonyos
NVD
EPSS 0% CVSS 8.9
HIGH POC This Week

Unauthenticated Arbitrary File Read via Null Byte Injection in DB Electronica Telecomunicazioni S.p.A. Rated high severity (CVSS 8.9), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.

PHP Authentication Bypass Mozart Next 3000 Firmware +21
NVD

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy