CVE Feed

    Dashboard / CVE / CVE-2021-27889

    CVE-2021-27889

    Cross-site Scripting (XSS) vulnerability in MyBB before 1.8.26 via Nested Auto URL when parsing messages.

    Published:Mar 15, 2021
    Last Modified:Nov 21, 2024
    EPS:Mar 15, 2021
    EPSS Score:0.02244
    CVSS Score:6.1

    Affected Products

    Vendor
    Mybb
    Product
    Mybb

    Exploits

    http://packetstormsecurity.com/files/161908/MyBB-1.8.25-Remote-Command-Execution.htmlhttps://blog.sonarsource.com/mybb-remote-code-execution-chainhttp://packetstormsecurity.com/files/161908/MyBB-1.8.25-Remote-Command-Execution.htmlhttps://blog.sonarsource.com/mybb-remote-code-execution-chainhttps://www.exploit-db.com/exploits/49696

    Related CVEs

    CVE-2026-45118 (CVSS 9.3) — MyBB is free and open source forum software. Prior to 1.8.40, the Contact module does not validate a redirect …
    CVE-2026-45117 (CVSS 9.8) — MyBB is free and open source forum software. From 1.8.13 until 1.8.40, the installer module does not properly …
    CVE-2026-45129 (CVSS 4.6) — MyBB is free and open source forum software. Prior to 1.8.40, the Admin CP Recovery Codes module does not vali…
    CVE-2026-45124 (CVSS 4.3) — MyBB is free and open source forum software. Prior to 1.8.40, the Mod CP Report Center does not check permissi…
    CVE-2026-45120 (CVSS 5.4) — MyBB is free and open source forum software. Prior to 1.8.40, the calendar module does not verify private even…
    CVE-2026-47245 (CVSS 4.3) — MyBB is free and open source forum software. Prior to 1.8.40, the User CP Buddy/Ignore List component does not…
    CVE-2026-45734 (CVSS 5.3) — MyBB is free and open source forum software. Prior to 1.8.40, the built-in CAPTCHA does not consistently enfor…
    CVE-2026-45125 (CVSS 5.3) — MyBB is free and open source forum software. Prior to 1.8.40, the Email User controller does not sanitize send…
    CVE-2026-45122 (CVSS 4.3) — MyBB is free and open source forum software. Prior to 1.8.40, the calendar module does not validate moderation…
    CVE-2026-45119 (CVSS 4.6) — MyBB is free and open source forum software. Prior to 1.8.40, the Admin CP UTF-8 Conversion module does not va…

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High