CVE-2024-38270

Session hijacking via low-entropy token generation

Published Sep 10, 2024 · Updated Sep 10, 2024

Insufficient entropy in Zyxel GS1900-10HP Firmware V2.80(AAZI.0)C0 allows remote attackers to guess a valid web session token. The web authentication token generator uses a low-entropy randomness function, making live session tokens guessable. Exploitation requires LAN access and multiple authenticated sessions to be active, and successful guessing grants access to an existing web session.

CVSS severity5.3
Medium
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Insufficient entropy in Zyxel GS1900-10HP Firmware V2.80(AAZI.0)C0 allows remote attackers to guess a valid web session token. The web authentication token generator uses a low-entropy randomness function, making live session tokens guessable. Exploitation requires LAN access and multiple authenticated sessions to be active, and successful guessing grants access to an existing web session.

The record

CVE
CVE-2024-38270
Published
Sep 10, 2024
Updated
Sep 10, 2024
Vendor
Zyxel Networks
Product
GS1900-10HP Firmware
Classifications
CWE-331, T1539
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 10, 2024CVE publishedPublication date reported by the CVE source.
  2. Sep 10, 2024Record 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=V2.80(AAZI.0)C0

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Zyxel Networks · GS1900-10HP Firmwareversion=V2.80(AAZI.0)C0

Published CVSS scores

5.3Zyxel CorporationCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
6.5NIST NVDCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

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.

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No observations available

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

Weakness, pattern, technique

CWE-331Insufficient Entropy
T1539Steal Web Session Cookie

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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