CVE-2021-45839

published 2022-04-25

CVE-2021-45839: It is possible to obtain the first administrator's hash set up on the system in Terramaster F4-210, F2-210 TOS 4.2.X (4.2.15-2107141517) as well as other…

Priority P3 50 medium 6.5 CVSS 3.1

AV N AC L PR L UI N S U C H I N A N

EXPLOIT

It is possible to obtain the first administrator's hash set up on the system in Terramaster F4-210, F2-210 TOS 4.2.X (4.2.15-2107141517) as well as other information such as MAC address, internal IP address etc. by performing a request to the /module/api.php?mobile/webNasIPS endpoint.

Affected

1 ranges

Vendor	Product	Version range	Fixed in
terra-master	tos	—	—

Detection & IOCs extracted from sources · hover to see the quote

url /module/api.php?mobile/webNasIPS↗

url /tos/index.php?app/del↗

• → Monitor for unauthenticated GET/POST requests to /module/api.php?mobile/webNasIPS — this endpoint leaks the first administrator's password hash, MAC address, and internal IP address without authentication. ↗
• → Detect requests to /tos/index.php?app/del as part of the chained RCE exploit (CVE-2021-45837); this endpoint is used for arbitrary command execution as root following session crafting. ↗
• → Alert on self-signed session cookies crafted using the target MAC address and user password hash (CVE-2021-45841); guest login abuse is possible with a null/empty hash even when guest accounts are disabled by default. ↗

• · Affected versions are TerraMaster TOS 4.2.15 and below (specifically confirmed on F4-210, F2-210 TOS 4.2.X / 4.2.15-2107141517). Ensure version scope is validated before deploying detections. ↗
• · CVE-2021-45839 is one link in a three-CVE chain (also involving CVE-2021-45841 for session crafting and CVE-2021-45837 for RCE); detections should cover all three endpoints for full coverage. ↗

CVSS provenance

nvd v3.1 6.5 MEDIUM CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

nvd v2.0 4.0 MEDIUM AV:N/AC:L/Au:S/C:P/I:N/A:N

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