CVE-2008-1255

CRITICAL

The ZyXEL P-660HW series router maintains authentication state by IP address, which allows remote attackers to bypass authentication by establishing a session from a source IP address of a previous...

Affects 1 product across 1 vendor.

BCS7.14
CVSS 2.010.0
EPSS3.9%
Percentile90th
PatchUnknown
CVSS Vector — Plain English Remotely exploitable over the network, low complexity.
CWE Weakness Definitions
CWE-264: Permissions, Privileges, and Access Controls

Broad class covering failures in permission enforcement. Deprecated in favor of CWE-284, CWE-862, CWE-863.

◆ AI Analysis — automated analysis, not human-reviewed

This vulnerability was disclosed in 2008. A critical vulnerability affects Zyxel systems (CVE-2008-1255). No public exploit code is currently available. Isolate affected systems if patching is not feasible.

BSID: BS-2008-GLOBAL-020634-C • Model: rule-based-v1 • Confidence: MEDIUM

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Frequently Asked Questions
What is CVE-2008-1255?
This vulnerability was disclosed in 2008. A critical vulnerability affects Zyxel systems (CVE-2008-1255). No public exploit code is currently available. Isolate affected systems if patching is not feasible.
What is the CVSS score for CVE-2008-1255?
CVE-2008-1255 has CVSS 10.0 (Critical). Vector: AV:N/AC:L/Au:N/C:C/I:C/A:C. EPSS: 3.9%.
Is CVE-2008-1255 actively exploited?
No confirmed active exploitation of CVE-2008-1255 as of 2026-09-25.
How do I remediate CVE-2008-1255?
Priority: MEDIUM.
What systems are affected by CVE-2008-1255?
CVE-2008-1255 affects: Zyxel.
Vulnerability Details
CVE IDCVE-2008-1255
BSIDBS-2008-GLOBAL-020634-C BreachSpider Global ID
CVSS VectorAV:N/AC:L/Au:N/C:C/I:C/A:C
Published2008-03-10
Last Modified2026-06-16
ICS Relevance85%
Weakness (CWE)
Permissions, Privileges, and Access Controls
Domains
NETWORK-INFRA
SourceNVD
Official Description

The ZyXEL P-660HW series router maintains authentication state by IP address, which allows remote attackers to bypass authentication by establishing a session from a source IP address of a previously authenticated user.

Source: NIST NVD / MITRE CVE Database

Attack Vector Analysis — CITED Relevance

Vulnerability details: The ZyXEL P-660HW series router maintains authentication state by IP address, which allows remote attackers to bypass authentication by establishing a session from a source IP address of a previously authenticated user. CVSS vector: AV:N/AC:L/Au:N/C:C/I:C/A:C.

Exploitation Likelihood: LOW

Affected Products
VendorProductFixed Version
Zyxel P-660Hw —
Remediation

No patch URL on record. Monitor vendor security advisories directly.

Threat Intelligence
● Threat Intelligence Validated: September 2026 | Threat Age: 6775 Days
CISA KEVNot in KEV catalog
Public ExploitNot confirmed
PoC CodeNot confirmed
AI Enrichment Record — provenance & audit hash
Modelrule-based-v1
ConfidenceMEDIUM
Enriched At2026-05-24
SHA-512 Audit Hash8bbef1bcc46ceebdef3789d4f4ba96a360eb8158c66a45704728ee2e8907d2d735283ef978543e6c5ffdb731a91ee5134d973ad2a4fb9f0a9292a5730ab78ae8
Related CVEs affecting Zyxel
CVE-2017-7964 10.0 Zyxel WRE6505 devices have a default TELNET password of 1234 for the root and... CVE-2008-1256 10.0 The ZyXEL P-660HW series router has "admin" as its default password, which al... CVE-2008-1160 9.8 ZyXEL ZyWALL 1050 has a hard-coded password for the Quagga and Zebra processe... CVE-2015-6016 9.8 ZyXEL P-660HW-T1 2 devices with ZyNOS firmware 3.40(AXH.0), PMG5318-B20A devi... CVE-2015-6018 9.8 The diagnostic-ping implementation on ZyXEL PMG5318-B20A devices with firmwar...
View all Zyxel CVEs →

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