csirt@kutim:~/threat-intel/cve/CVE-2026-42534

Katalog CVE

CVSS 5.3 · Medium EPSS 0,72%

Kerentanan Expected Behavior Violation pada nlnetlabs unbound. Skor CVSS 3.1 5.3 (Medium) menurut NVD.

Deskripsi (NVD)

NLnet Labs Unbound up to and including version 1.25.0 has a vulnerability in the jostle logic that could defeat its purpose and degrade resolution performance. Retransmits of the same query could renew the age of slow running queries and not allow the jostle logic to see them as aged and potential targets for replacement with new queries. An adversary who can query a vulnerable Unbound and who can control a domain name server that replies slowly and/or maliciously to Unbound's queries can exploit the vulnerability and degrade the resolution performance of Unbound. When Unbound's 'num-queries-per-thread' reaches its limit, the jostle logic kicks in. When a new query comes in, half of the available queries that are also slow to resolve are candidates for replacement. The vulnerability then happens because duplicate queries that need resolution would skew the aging result by using the timestamp of the latest duplicate query instead of the original one that started the resolution effort. Cache and local data response performance remains unaffected. Coordinated attacks could raise this to a denial of resolution service. Unbound 1.25.1 contains a patch with a fix to attach an initial, non-updatable start time for incoming queries that allow the jostle logic to work as intended.

Rincian

Terbit di NVD
20 Mei 2026
Terakhir diubah
1 September 2026
Status NVD
Modified
CVSS 3.1
5.3 (Medium), sumber NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L · uraikan di kalkulator
Jenis kelemahan (CWE)
CWE-440: Expected Behavior Violation
CWE-911: Improper Update of Reference Count
EPSS (30 hari)
0,72% peluang dieksploitasi; lebih tinggi dari 52,5% CVE lain

Produk dan versi terdampak

VendorProdukVersi terdampak
nlnetlabs unbound Semua versi sebelum 1.25.1

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

Sumber: NVD · CVE.org · EPSS. Halaman ini disusun otomatis dari data tersebut; pembaruan terakhir 5 Okt 2026, 20:11 WITA. Kalau sistem di Perangkat Daerah memakai produk ini dan butuh bantuan, laporkan lewat kanal pelaporan.