The insufficiently protected credentials vulnerability in the CLI command of the USG FLEX H series uOS firmware version V1.21 and earlier v…

published 2024-10-22 2 y ago modified 2026-06-17 4 mo ago also EUVD-2024-50086

cvss: 5.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 4%
public exploits: 0; none known

The insufficiently protected credentials vulnerability in the CLI command of the USG FLEX H series uOS firmware version V1.21 and earlier versions could allow an authenticated local attacker to gain privilege escalation by stealing the authentication token of a login administrator. Note that this attack could be successful only if the administrator has not logged out.

Patch / fix

fixed in 1

zyxel uos 1.30

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 2 y ago (2024-10-22)

Exploit prediction

0.15% chance of exploitation in the next 30 days, higher than 4% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
NVD	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

Zyxel USG FLEX H series uOS firmware
zyxel usg_flex_700h_firmware

Classification

Weakness

CWE-522 Insufficiently Protected Credentials

References

zyxel.com /global/en/support/security-advisories/zyxel-security-advisory-for-insufficiently-protected-credentials-vulner
vendor-advisory

Sources

CVE List CVE-2024-9677
NVD CVE-2024-9677

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Summary