CVE-2021-3337

published 2021-01-28

CVE-2021-3337: The Hide-Thread-Content plugin through 2021-01-27 for MyBB allows remote attackers to bypass intended content-reading restrictions by clicking on reply or…

Priority P2 60 high 7.5 CVSS 3.1

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

EXPLOIT

The Hide-Thread-Content plugin through 2021-01-27 for MyBB allows remote attackers to bypass intended content-reading restrictions by clicking on reply or quote in the postbit.

Affected

1 ranges

Vendor	Product	Version range	Fixed in
hide_thread_content_project	hide_thread_content	—	—

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

• → Hidden thread content is exposed when a user clicks the reply or quote button in the postbit — monitor for unauthenticated or non-replying users accessing quote/reply endpoints that return protected content ↗
• → The bypass is triggered by clicking reply or quote in the postbit, causing hidden content to appear inside [quote] brackets — inspect responses to reply/quote actions for content that should be gated behind a reply requirement ↗

• · Vulnerability affects Hide-Thread-Content plugin through version 1.0 (last updated 2021-01-27) for MyBB; only installations with this plugin active are affected ↗
• · No authentication or special privilege is required to exploit this — any remote attacker can trigger the disclosure via the standard reply/quote UI interaction ↗

CVSS provenance

nvd v3.1 7.5 HIGH CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

nvd v2.0 5.0 MEDIUM AV:N/AC:L/Au:N/C:P/I:N/A:N

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