CVE WatchJul 15, 2026

CVE-2026-42959

NLnet Labs Unbound up to and including version 1.25.0 has a denial of service vulnerability in the DNSSEC validator that can lead to a crash

CVSS

7.5

High

EPSS

0.8%

p52

KEV

—

Exploit Today

0-100

Published: May 20, 2026 · Last modified: Jul 15, 2026 · CWE-824

EPSS · 30d

0.8%EPSS · 30 days0.8%

2026-06-302026-07-16

Technical description

NLnet Labs Unbound up to and including version 1.25.0 has a denial of service vulnerability in the DNSSEC validator that can lead to a crash given malicious upstream replies. When Unbound constructs chase-reply messages for validation, the code uses the wrong counter to calculate write offsets for ADDITIONAL section rrsets. DNAME duplication could increase the ANSWER section count and authority filtering could decrease the AUTHORITY section count and create an uninitialized array slot. Combining these two, the validator later dereferences this uninitialized pointer, causing an immediate process crash. An adversary controlling a DNSSEC-signed domain can trigger this bug with a single query by configuring a DNAME chain with unsigned CNAMEs and a response containing unsigned AUTHORITY records alongside signed ADDITIONAL glue records. Unbound 1.25.1 contains a patch with a fix to use the proper counters to calculate the write offsets.

Official references

Related CVEs

CVECVSSEPSSKEVRExploitTitleMod.

CVE-2026-34977.5 HIG

80.3%

——24Vulnerability in the OpenSSH GSSAPI delta included in various Linux distributions. This vulnerability affects the GSSAPI patches added by various Linux distributions and does not affect the OpenSSH upstream project itself. The usage of sshpkt_disconnect() on an error, which does not terminate the process, allows an attacker to send an unexpected GSSAPI message type during the GSSAPI key exchange to the server, which will call the underlying function and continue the execution of the program without setting the related connection variables. As the variables are not initialized to NULL the code later accesses those uninitialized variables, accessing random memory, which could lead to undefined behavior. The recommended workaround is to use ssh_packet_disconnect() instead, which does terminate the process. The impact of the vulnerability depends heavily on the compiler flag hardening configuration.2d CVE-2026-21005.3 MED

63.5%

——19A flaw was found in p11-kit. A remote attacker could exploit this vulnerability by calling the C_DeriveKey function on a remote token with specific IBM kyber or IBM btc derive mechanism parameters set to NULL. This could lead to the RPC-client attempting to return an uninitialized value, potentially resulting in a NULL dereference or undefined behavior. This issue may cause an application level denial of service or other unpredictable system states.3d CVE-2026-457364.4 MED

50.6%

——15ws is an open source WebSocket client and server for Node.js. Prior to 8.20.1, the websocket.close() implementation is vulnerable to uninitialized memory disclosure when a TypedArray is passed as the reason argument. This vulnerability is fixed in 8.20.1.2d CVE-2026-67497.5 HIG

32.6%

——10Information disclosure due to uninitialized memory in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 150, Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.2d CVE-2026-67489.8 CRI

32.1%

——10Uninitialized memory in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.2d CVE-2026-286917.5 HIG

27.6%

——8ImageMagick is free and open-source software used for editing and manipulating digital images. Prior to versions 7.1.2-16 and 6.9.13-41, an uninitialized pointer dereference vulnerability exists in the JBIG decoder due to a missing check. This vulnerability is fixed in 7.1.2-16 and 6.9.13-41.2d