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🎯 CVE-2026-81000 🇪🇺 EUVD
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CVE-2026-81000 | In the Linux kernel, the following vulnerability has been resolved: net: tun: bound receive headroom tun_get_user() uses tun->align both as skb headroom and when choosing how much packet data to keep linear. OVS can propagate an oversized headroom request from another port to TUN or TAP. When align is larger than the usable space in a one-page skb head, SKB_MAX_HEAD(align) underflows and the result becomes negative when stored in good_linear. That value la

In the Linux kernel, the following vulnerability has been resolved:

net: tun: bound receive headroom

tun_get_user() uses tun->align both as skb headroom and when choosing how
much packet data to keep linear. OVS can propagate an oversized headroom
request from another port to TUN or TAP.

When align is larger than the usable space in a one-page skb head,
SKB_MAX_HEAD(align) underflows and the result becomes negative when stored
in good_linear. That value later wraps when assigned to the size_t linear
variable, and tun_alloc_skb() can place skb->data outside the allocated
head.

Bound the headroom stored by TUN to the one-page skb-head budget and the
largest non-sentinel 16-bit skb header offset. Leave one linear byte for
raw TUN and a complete Ethernet header for TAP, including NET_IP_ALIGN.

Also pull the raw-TUN protocol byte and the TAP Ethernet header before
accessing them, so these checks remain safe for nonlinear skbs supplied by
other allocation paths.

Klassifikation & Betroffenheit:
Linux Linux patch: 7.2.4Linux eaea34b23c46bf17b4a5638be69ab3561854f34b <379d85c7f25f3e05a428225e6b8a65613c6e9b9dLinux eaea34b23c46bf17b4a5638be69ab3561854f34b <708e87937de93f445225c134a2e20519f9b4ce60Linux patch: 6.1.188Linux patch: 6.6.157Linux patch: 5.15.221Linux 4.6Linux eaea34b23c46bf17b4a5638be69ab3561854f34b <ad715e713610d2d5473c3a6498c825ccecf26491
Improper Control of Generation of Code ('Code Injection') 🎯 Medium

The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.

🛡️ Empfohlene Mitigation: Refactor your program so that you do not have to dynamically generate code.
Vollständige Definition bei MITRE ➔
⚔️ Typische Angriffsmuster (CAPEC):
CAPEC-35 · Leverage Executable Code in Non-Executab… (Very High) CAPEC-77 · Manipulating User-Controlled Variables (Very High) CAPEC-242 · Code Injection (High)
🎯 ATT&CK-Techniken (Kill-Chain-Verhalten):
T1027.006 · Obfuscated Files or Information: H… T1027.009 · Obfuscated Files or Information: E… T1564.009 · Hide Artifacts: Resource Forking
🧩 Ähnliche Schwachstellen (Hersteller/Klasse/Score-Band):
CVE-2026-90049 9.3 CVE-2026-89930 9.3 CVE-2026-89918 9.3 CVE-2026-89916 9.3 CVE-2026-89915 9.3
🧪 Exploit-Evidenz:
🐙 0xBlackash/CVE-2026-81000
🩹 Patch verfügbar (OSV):
🩹 Kernel ≥ 5.10.270 🩹 Kernel ≥ 5.15.221 🩹 Kernel ≥ 6.1.188 🩹 Kernel ≥ 6.6.157 🩹 Kernel ≥ 6.12.109 🩹 Kernel ≥ 6.18.50
📰 Eigene Berichterstattung: ➔ CVE-2026-81000 | Linux Kernel up to 6.12.108/6.18.49/7.2.3 Tun tun_get_user alig
📚 Referenzen & Quellen:
🇪🇺 Original-Eintrag (ENISA EUVD) 🇺🇸 NVD-Eintrag
Ausnutzungs-Zeitleiste:
CVSS-Vektor-Analyse: 7.8
AV · Angriffsvektor Lokal
AC · Komplexität Gering
PR · Privilegien Gering
UI · Interaktion Keine
S · Scope Unverändert
C · Vertraulichkeit Hoch
I · Integrität Hoch
A · Verfügbarkeit Hoch
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Veröffentlicht:11.09.2026
Aktualisiert:14.09.2026 13:18
Assigner (CNA):Linux
EUVD-ID:EUVD-2026-76323
Quellen: 🇪🇺 EUVD-Datenbank (ENISA) + 🇺🇸 NVD-Anreicherung · 24-h-Cache
CWE-94: Code Injection ✓ Offizieller Patch / Advisory verfügbar
💡 Gegenmaßnahme: Kernel-Paket aktualisieren (apt upgrade linux-image / yum update kernel) und System neu starten.
🔴 Live Security Advisory & EPSS Exploit Radar

Zero-Day & Vulnerability Intelligence Hub

Echtzeit-Tracking mit EPSS Exploit-Wahrscheinlichkeiten, Angriffsvektor-Decodern und KI-Patch-Anleitungen.

🟢 SSE Realtime Synchronisiert ⚡ REST API (JSON) 📡 Digest (RSS) 📡 RSS Feed
367k+ 🇪🇺 EUVD-Datenbank
0 🔴 Critical im Radar
0 ⚠️ CISA KEV
0 🔓 Aktiv ausgenutzt
0 🧪 PoC verfügbar
7 🆕 Neu im KEV (7 T)
📊 Historien-Charts — Criticals-Trend · Vendors · EPSS-Verteilung
🔴 Criticals pro Monat (12 M) 2025-09: 81 2025-10: 317 2025-11: 257 2025-12: 426 2026-01: 431 2026-02: 417 2026-03: 649 2026-04: 574 2026-05: 683 2026-06: 941 2026-07: 1327 2026-08: 1828 2026-09: 1022 8.953 Criticals gesamt
🏢 Top-Vendor-Veröffentlichungen (6 M) Adobe Apple Google Linux Microsoft Oracle Corporation
● Adobe ● Apple ● Google ● Linux ● Microsoft ● Oracle
📈 EPSS-Verteilung (Messungen)
Tier2026-09-022026-09-20
≥90 %0489
≥50 %01477
≥10 %00
<10 %3000
📈 EPSS-Riser (7 Tage) CVE-2021-38156 ↑ 3.97 % CVE-2025-32463 ↑ 1.62 % CVE-2024-32640 ↑ 1.13 %
Frühindikator · FIRST.org
Datenquellen & Methodik: Primärquelle ist die EUVD der ENISA (laufender Datenbank-Sync, alle 15 Minuten), abgeglichen mit dem CISA-KEV-Katalog und der NVD — Detail-Dossiers reichern fehlende Felder live per NVD an — mit Fallback auf CIRCL vulnerability-lookup (EU/Non-Profit, aggregiert CVE-, GitHub- und OSV-Advisories). Der CISA-KEV-Katalog (Known Exploited Vulnerabilities, ~1.700 aktiv ausgenutzte Schwachstellen) wird bei jedem Sync vollständig neu geladen und kreuzreferenziert — filterbar über die KEV-Pille. CVSS 3.1 wird nach Ampel-Logik aus Verteidigersicht dekodiert; EPSS bezeichnet die 30-Tage-Exploit-Wahrscheinlichkeit (FIRST.org).
🇪🇺 ENISA EUVD 🇺🇸 NVD ⚠️ CISA KEV ⚡ EPSS
Ökosystem & Hersteller Bedrohungs-Matrix:
Schweregrad & Status:
Hersteller (Datenbank-weit, 96.577 Einträge):
EPSS-Schwelle:
Quelle:
Schwachstellen-Kategorie (CWE):
🔍
EPSS 0.2%
CVE-2026-81000 💻 Lokal 🔑 Geringe Nutzerrechte nötig
Linux

CVE-2026-81000 | In the Linux kernel, the following vulnerability has been resolved: net: tun: bound receive headroom tun_get_user() uses tun->align both as skb headroom and when choosing how much packet data to keep linear. OVS can propagate an oversized headroom request from another port to TUN or TAP. When align is larger than the usable space in a one-page skb head, SKB_MAX_HEAD(align) underflows and the result becomes negative when stored in good_linear. That value la

In the Linux kernel, the following vulnerability has been resolved: net: tun: bound receive headroom tun_get_user() uses tun->align both as skb headroom and when choosing how much packet data to keep linear. OVS can propagate an oversized

CWE-94: Code Injection ✓ Offizieller Patch / Advisory verfügbar
💡 Gegenmaßnahme: Kernel-Paket aktualisieren (apt upgrade linux-image / yum update kernel) und System neu starten.
11.09.2026
🛡️ Details ➔