CVE-2026-42944
גבוהה 7.5
תיאור (מקור, אנגלית)
NLnet Labs Unbound 1.14.0 up to and including version 1.25.0 has a vulnerability that results in heap overflow when encoding multiple NSID and/or DNS Cookie EDNS and/or EDNS Padding options in the reply packet. The relevant options ('nsid', 'answer-cookie', 'pad-responses' (default)) need to be enabled for the vulnerability to be exploited. An adversary who can query Unbound can exploit the vulnerability by attaching multiple NSID and/or DNS Cookie EDNS and/or EDNS Padding options to the query. A flaw in the size calculation of the EDNS field truncates the correct value which allows the encoder to overflow the available space when writing. Those two combined lead to a heap overflow write of Unbound controlled data and eventually a crash. Unbound 1.25.1 contains a patch with a fix to de-duplicate the EDNS options and a fix to prevent truncation of the EDNS field size calculation.
מדדים
- CVSS 3.1
-
7.5 (HIGH)
מקור הציון: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
8.7 (HIGH)
מקור הציון: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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:Red - EPSS — סבירות ניצול
- 1% (אחוזון 100) נכון ל-4/8/2026
- CWE
- CWE-197, CWE-787
מוצרים מושפעים
nlnetlabs: unbound
קישורים
- https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-42944.txt MitigationVendor Advisory
- https://access.redhat.com/errata/RHSA-2026:19752
- https://access.redhat.com/errata/RHSA-2026:23231
- https://access.redhat.com/errata/RHSA-2026:24365
- https://access.redhat.com/errata/RHSA-2026:24369
- https://access.redhat.com/security/cve/CVE-2026-42944
- https://bugzilla.redhat.com/show_bug.cgi?id=2479774
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42944.json