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CVE archive

September 2021

Browse CVE records published in September 2021, with severity, affected products, CWE, KEV, and source-backed vulnerability context.

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Showing 50 of 1832 matching CVEs · Page 1 of 37.

Unknown · CVSS Not scored

CVE-2021-36581: Kooboo CMS 2.1.1.0 is vulnerable to Insecure file upload.

Kooboo CMS 2.1.1.0 is vulnerable to Insecure file upload. It is possible to upload any file extension to the server. The server does not verify the extension of the file and the tester was able to upload an aspx to the server.

Published Sep 14, 2021 · Updated Jul 9, 2026

Unknown · CVSS Not scored

CVE-2021-26333: AMD Chipset Driver Information Disclosure Vulnerability

An information disclosure vulnerability exists in AMD Platform Security Processor (PSP) chipset driver. The discretionary access control list (DACL) may allow low privileged users to open a handle and send requests to the driver resulting in a potential data leak from uninitialized physical pages.

Published Sep 21, 2021 · Updated May 28, 2026

Medium · CVSS 5.3

CVE-2021-3806: Path Traversal in Pardus Software Center

A path traversal vulnerability on Pardus Software Center's "extractArchive" function could allow anyone on the same network to do a man-in-the-middle and write files on the system.

Published Sep 18, 2021 · Updated May 18, 2026

Unknown · CVSS Not scored

CVE-2021-41617: sshd in OpenSSH 6.2 through 8.x before 8.8, when certain non-default configurations are used, allows privil...

sshd in OpenSSH 6.2 through 8.x before 8.8, when certain non-default configurations are used, allows privilege escalation because supplemental groups are not initialized as expected. Helper programs for AuthorizedKeysCommand and AuthorizedPrincipalsCommand may run with privileges associated with group memberships of the sshd process, if the configuration specifies running the command as a different user.

Published Sep 26, 2021 · Updated May 12, 2026

Medium · CVSS 6.9

CVE-2021-36845: YITH Maintenance Mode (WordPress plugin) <= 1.3.8 - Multiple Authenticated Stored Cross-Site Scripting (XSS) vulnerabilities

Multiple Authenticated Stored Cross-Site Scripting (XSS) vulnerabilities in YITH Maintenance Mode (WordPress plugin) versions <= 1.3.8, there are 46 vulnerable parameters that were missed by the vendor while patching the 1.3.7 version to 1.3.8. Vulnerable parameters: 1 - "Newsletter" tab, &yith_maintenance_newsletter_submit_label parameter: payload should start with a single quote (') symbol to break the context, i.e.: NOTIFY ME' autofocus onfocus=alert(/Visse/);// v=' - this payload will be auto triggered while admin visits this page/tab. 2 - "General" tab issues, vulnerable parameters: &yith_maintenance_message, &yith_maintenance_custom_style, &yith_maintenance_mascotte, &yith_maintenance_title_font[size], &yith_maintenance_title_font[family], &yith_maintenance_title_font[color], &yith_maintenance_paragraph_font[size], &yith_maintenance_paragraph_font[family], &yith_maintenance_paragraph_font[color], &yith_maintenance_border_top. 3 - "Background" tab issues, vulnerable parameters: &yith_maintenance_background_image, &yith_maintenance_background_color. 4 - "Logo" tab issues, vulnerable parameters: &yith_maintenance_logo_image, &yith_maintenance_logo_tagline, &yith_maintenance_logo_tagline_font[size], &yith_maintenance_logo_tagline_font[family], &yith_maintenance_logo_tagline_font[color]. 5 - "Newsletter" tab issues, vulnerable parameters: &yith_maintenance_newsletter_email_font[size], &yith_maintenance_newsletter_email_font[family], &yith_maintenance_newsletter_email_font[color], &yith_maintenance_newsletter_submit_font[size], &yith_maintenance_newsletter_submit_font[family], &yith_maintenance_newsletter_submit_font[color], &yith_maintenance_newsletter_submit_background, &yith_maintenance_newsletter_submit_background_hover, &yith_maintenance_newsletter_title, &yith_maintenance_newsletter_action, &yith_maintenance_newsletter_email_label, &yith_maintenance_newsletter_email_name, &yith_maintenance_newsletter_submit_label, &yith_maintenance_newsletter_hidden_fields. 6 - "Socials" tab issues, vulnerable parameters: &yith_maintenance_socials_facebook, &yith_maintenance_socials_twitter, &yith_maintenance_socials_gplus, &yith_maintenance_socials_youtube, &yith_maintenance_socials_rss, &yith_maintenance_socials_skype, &yith_maintenance_socials_email, &yith_maintenance_socials_behance, &yith_maintenance_socials_dribble, &yith_maintenance_socials_flickr, &yith_maintenance_socials_instagram, &yith_maintenance_socials_pinterest, &yith_maintenance_socials_tumblr, &yith_maintenance_socials_linkedin.

Published Sep 27, 2021 · Updated Apr 28, 2026

Medium · CVSS 5.9

CVE-2021-22947: When curl >= 7.20.0 and <= 7.78.0 connects to an IMAP or POP3 server to retrieve data using STARTTLS to upg...

When curl >= 7.20.0 and <= 7.78.0 connects to an IMAP or POP3 server to retrieve data using STARTTLS to upgrade to TLS security, the server can respond and send back multiple responses at once that curl caches. curl would then upgrade to TLS but not flush the in-queue of cached responses but instead continue using and trustingthe responses it got *before* the TLS handshake as if they were authenticated.Using this flaw, it allows a Man-In-The-Middle attacker to first inject the fake responses, then pass-through the TLS traffic from the legitimate server and trick curl into sending data back to the user thinking the attacker's injected data comes from the TLS-protected server.

Published Sep 29, 2021 · Updated Apr 16, 2026

High · CVSS 7.5

CVE-2021-22946: A user can tell curl >= 7.20.0 and <= 7.78.0 to require a successful upgrade to TLS when speaking to an IMA...

A user can tell curl >= 7.20.0 and <= 7.78.0 to require a successful upgrade to TLS when speaking to an IMAP, POP3 or FTP server (`--ssl-reqd` on the command line or`CURLOPT_USE_SSL` set to `CURLUSESSL_CONTROL` or `CURLUSESSL_ALL` withlibcurl). This requirement could be bypassed if the server would return a properly crafted but perfectly legitimate response.This flaw would then make curl silently continue its operations **withoutTLS** contrary to the instructions and expectations, exposing possibly sensitive data in clear text over the network.

Published Sep 29, 2021 · Updated Apr 16, 2026

High · CVSS 8.8 · CISA KEV

CVE-2021-40444: Microsoft MSHTML Remote Code Execution Vulnerability

<p>Microsoft is investigating reports of a remote code execution vulnerability in MSHTML that affects Microsoft Windows. Microsoft is aware of targeted attacks that attempt to exploit this vulnerability by using specially-crafted Microsoft Office documents.</p> <p>An attacker could craft a malicious ActiveX control to be used by a Microsoft Office document that hosts the browser rendering engine. The attacker would then have to convince the user to open the malicious document. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.</p> <p>Microsoft Defender Antivirus and Microsoft Defender for Endpoint both provide detection and protections for the known vulnerability. Customers should keep antimalware products up to date. Customers who utilize automatic updates do not need to take additional action. Enterprise customers who manage updates should select the detection build 1.349.22.0 or newer and deploy it across their environments. Microsoft Defender for Endpoint alerts will be displayed as: “Suspicious Cpl File Execution”.</p> <p>Upon completion of this investigation, Microsoft will take the appropriate action to help protect our customers. This may include providing a security update through our monthly release process or providing an out-of-cycle security update, depending on customer needs.</p> <p>Please see the <strong>Mitigations</strong> and <strong>Workaround</strong> sections for important information about steps you can take to protect your system from this vulnerability.</p> <p><strong>UPDATE</strong> September 14, 2021: Microsoft has released security updates to address this vulnerability. Please see the Security Updates table for the applicable update for your system. We recommend that you install these updates immediately. Please see the FAQ for important information about which updates are applicable to your system.</p>

Published Sep 15, 2021 · Updated Mar 11, 2026

Medium · CVSS 6.7

CVE-2021-33285: In NTFS-3G versions < 2021.8.22, when a specially crafted NTFS attribute is supplied to the function ntfs_g...

In NTFS-3G versions < 2021.8.22, when a specially crafted NTFS attribute is supplied to the function ntfs_get_attribute_value, a heap buffer overflow can occur allowing for memory disclosure or denial of service. The vulnerability is caused by an out-of-bound buffer access which can be triggered by mounting a crafted ntfs partition. The root cause is a missing consistency check after reading an MFT record : the "bytes_in_use" field should be less than the "bytes_allocated" field. When it is not, the parsing of the records proceeds into the wild.

Published Sep 7, 2021 · Updated Dec 3, 2025