CVE-2026-49008: Device Firmware Information Disclosure Flaw

CVE-2026-49008 Overview

CVE-2026-49008 describes a firmware credential exposure issue affecting a ZTE device. Unencrypted information stored in the device firmware allows an attacker to retrieve credentials tied to the integrity verification of a specific application function. The weakness is categorized under [CWE-321] Use of Hard-coded Cryptographic Key. Because the credentials govern integrity verification rather than confidentiality, successful extraction primarily enables tampering with the affected application function. The issue is tracked in the ZTE Security Bulletin #2171542593031803093.

Critical Impact
An authenticated network-adjacent attacker can extract firmware-embedded credentials and subvert integrity checks that protect a specific application function on the device.

Affected Products

ZTE device firmware referenced in ZTE Security Bulletin #2171542593031803093
Specific product models and versions: Not Available in the NVD entry
Consult the vendor advisory for the authoritative affected-version list

Discovery Timeline

2026-08-07 - CVE-2026-49008 published to NVD
2026-08-07 - Last updated in NVD database

Technical Details for CVE-2026-49008

Vulnerability Analysis

The vulnerability stems from cryptographic material being stored in device firmware without encryption. An attacker who accesses the firmware image can parse it and recover credentials that the device uses to verify the integrity of a specific application function. Because the credential is embedded and shared across devices running the same firmware, extraction from a single unit compromises the integrity check on all similarly provisioned devices. The scope of the flaw is limited to integrity: the CVSS vector reports no confidentiality or availability impact, but a high integrity impact. This aligns with [CWE-321], where hard-coded keys undermine any security control that depends on them.

Root Cause

The root cause is the storage of integrity-verification credentials as unencrypted data inside the firmware image. Firmware distributed to customers or retrievable through vendor channels can be reverse-engineered to reveal these secrets. Effective mitigation requires provisioning per-device keys, storing secrets in a secure element or trusted execution environment, and rotating any credential exposed through firmware extraction.

Attack Vector

The attack requires network access and low-level privileges on the target. After obtaining the firmware image, the attacker locates the embedded credential using static analysis techniques such as string extraction, entropy analysis, or symbol lookup in the unpacked firmware. With the credential in hand, the attacker can forge or alter data that the vulnerable application function accepts, bypassing the integrity verification the credential was intended to enforce.

No public proof-of-concept exploit is currently associated with this CVE, and it is not listed in the CISA Known Exploited Vulnerabilities catalog. The EPSS data at publication indicates a low near-term exploitation probability.

Detection Methods for CVE-2026-49008

Indicators of Compromise

Unexpected modifications to files, configuration blobs, or update payloads processed by the affected application function
Successful acceptance by the device of manipulated data that should have failed integrity verification
Firmware images observed being downloaded or exfiltrated from management interfaces by non-administrative accounts
Log entries showing integrity verification passing on artifacts that internal auditing flags as altered

Detection Strategies

Compare hashes of on-device application components against vendor-published reference values on a scheduled basis
Monitor management-plane sessions for firmware retrieval operations that fall outside approved change windows
Alert on repeated low-privilege authentication events preceding firmware download or configuration write actions

Monitoring Recommendations

Centralize device syslog and management-plane audit logs for correlation across the fleet
Baseline normal administrative access patterns and flag deviations, particularly firmware read operations
Track vendor advisories from ZTE and re-scan the environment when new firmware versions or IOCs are published

How to Mitigate CVE-2026-49008

Immediate Actions Required

Review the ZTE Security Bulletin #2171542593031803093 and identify devices running affected firmware
Restrict management-interface access to a dedicated administrative network segment
Rotate any operator credentials that could be used to reach the device management plane
Inventory who holds copies of the firmware image and remove unnecessary distribution

Patch Information

Apply the firmware update referenced in the ZTE security bulletin once available for the affected model. The NVD entry does not list a fixed version at publication; validate the target firmware build against the vendor advisory before rollout. After patching, confirm that any credentials previously exposed through the vulnerable firmware are rotated on the device.

Workarounds

Limit network reachability to the device management plane using ACLs and firewall rules until firmware is updated
Require multi-factor authentication for administrator accounts that can retrieve firmware or configuration
Enable and forward device audit logs to a central collector to detect exploitation attempts
Where supported, disable or restrict the specific application function protected by the exposed integrity credential until the vendor fix is deployed

bash

# Example: restrict management access to a jump host with an ACL entry
# (adapt syntax to the specific ZTE platform in use)
configure terminal
access-list mgmt-acl permit tcp host 10.10.0.5 any eq 22
access-list mgmt-acl deny  ip any any log
interface management0
 ip access-group mgmt-acl in
end
write memory