جزئیات آسیب‌پذیری
CVE-2026-42959
Crash during DNSSEC validation of malicious content
شرح رسمی (انگلیسی)
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.
امتیازهای CVSS
| امتیاز | نسخه | منبع | بردار |
|---|---|---|---|
| 8.7بالا | 4.0 | CVEProject cvelistV5 (CNA) (NLnet Labs) | 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/U:Red |
| 7.5بالا | 3.1 | CVEProject cvelistV5 (CNA) (redhat-SADP) | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
محصولات آسیب‌پذیر
| فروشنده | محصول | نسخه‌ها | منبع |
|---|---|---|---|
| NLnet Labs | Unbound | v < 1.25.1 | CVEProject cvelistV5 (CNA) |
| Red Hat | Red Hat Enterprise Linux 7 | همه | CVEProject cvelistV5 (CNA) |
| Red Hat | Red Hat OpenShift Container Platform 4 | همه | CVEProject cvelistV5 (CNA) |
منابع و راهنماها
۸- https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-42959.txt vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-42959 vdb-entryx_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2479806 issue-trackingx_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42959.json x_sadp-csaf-vex
- https://access.redhat.com/errata/RHSA-2026:23231 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:24365 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:24369 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:19752 vendor-advisoryx_refsource_REDHAT
اطلاعات
- تاریخ انتشار
- ۱۴۰۵/۰۲/۳۰
- آخرین به‌روزرسانی
- ۱۴۰۵/۰۶/۱۰
- وضعیت
- منتشرشده
- صادرکننده (CNA)
- NLnet Labs
پیش‌بینی بهره‌برداری (EPSS)
ارزیابی SSVC (CISA)
- قابل خودکارسازی
- بله
- وضعیت بهره‌برداری
- ندارد
- اثر فنی
- جزئی
ضعف‌ها (CWE)
- CWE-824Access of Uninitialized Pointer