CVE-2023-49262Network attack vector

Authentication bypass via overflowing cookie field

Published Jan 12, 2024 · Updated Jun 3, 2025

Integer overflow in Hongdian H8951-4G-ESP firmware before 2310271149 allows remote attackers to bypass authentication via a crafted cookie. The authentication-cookie handler overflows while processing an oversized authentication field, causing the authentication mechanism to accept the request. A user session must already be active on the router, after which the bypass grants access in that authenticated session's context.

CVSS severity9.8
Critical
EPSS probability0.67%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Integer overflow in Hongdian H8951-4G-ESP firmware before 2310271149 allows remote attackers to bypass authentication via a crafted cookie. The authentication-cookie handler overflows while processing an oversized authentication field, causing the authentication mechanism to accept the request. A user session must already be active on the router, after which the bypass grants access in that authenticated session's context.

The record

CVE
CVE-2023-49262
Published
Jan 12, 2024
Updated
Jun 3, 2025
Vendor
Hongdian
Product
H8951-4G-ESP Firmware
Classifications
CWE-190, CWE-287, CAPEC-115, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 12, 2024CVE publishedPublication date reported by the CVE source.
  2. Jun 3, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <2310271149

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Hongdian · H8951-4G-ESP Firmwareversion=0 <2310271149

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-190Integer Overflow or Wraparound
CWE-287Improper Authentication
CAPEC-115Authentication Bypass
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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