The Disdain exploit kit appears in the threat landscape

CVE-2013-2551 is a use-after-free memory corruption flaw (CWE-416) in Microsoft Internet Explorer. An attacker triggers it by luring a user to a crafted website that causes the browser to access an object that has already been deleted from memory. Successful exploitation allows the attacker to execute arbitrary code on the victim machine, typically in the context of the logged-in user. All Internet Explorer deployments are potentially affected; the source data does not specify version ranges, but the flaw is best known as a long-lived legacy-browser issue exploited by drive-by exploit kits. The vulnerability is confirmed to be exploited in the wild: it is listed in CISA KEV (added 2022-03-28) with known ransomware use, and EPSS assigns it a 74.1% probability of exploitation in the next 30 days (99th percentile).

Do: Apply Microsoft updates for Internet Explorer per vendor instructions, as required by the CISA KEV listing, prioritizing any Windows systems still using IE or IE-based components. As interim mitigation, restrict browsing to trusted sites and ensure users are not running as administrators for routine web activity. Audit legacy environments for obsolete IE usage and migrate those systems to a supported, actively patched browser where updates are no longer feasible.

CVE-2014-6332 is a memory-corruption flaw (CWE-119) in OleAut32.dll, the OLE Automation component shipped with Microsoft Windows, in which OLE automation arrays are mishandled, allowing out-of-bounds memory access. A remote attacker triggers it by luring a user to a crafted website whose script (typically executed through Internet Explorer) calls into the vulnerable OLE Automation code, corrupting memory on the victim machine. Successful exploitation yields remote code execution with the privileges of the logged-on user, generally giving the attacker full control of the workstation. Because OleAut32.dll is a core OS component, essentially every Windows client and server in circulation at the time was affected; Microsoft addressed it in the November 2014 security updates (MS14-064). The flaw is listed in CISA's Known Exploited Vulnerabilities catalog (added 2022-03-25), indicating known in-the-wild exploitation, and EPSS assigns a 95% probability of exploitation within 30 days (100th percentile); no public PoC is tracked in the source data.

Do: Apply Microsoft's November 2014 Windows/OLE security updates (MS14-064) across all Windows clients and servers, prioritizing internet-facing systems and workstations used for web browsing, and confirm the patched OleAut32.dll is present via patch-management or vulnerability-scanner checks. Because the flaw is KEV-listed and exploitable in a drive-by web-attack scenario, treat any remaining unpatched Windows host as high risk and isolate legacy systems that cannot be updated.

CVE-2015-2419 is a memory corruption flaw (CWE-119) in the JScript engine used by Microsoft Internet Explorer, allowing remote attackers to execute arbitrary code or cause a denial of service through a crafted website. It is triggered when a user visits an attacker-controlled page whose JScript content corrupts memory in the affected browser process. A successful attacker gains remote code execution in the context of the logged-on user (or crashes the browser), which makes drive-by and exploit-kit delivery routes viable. Any Windows user running the affected versions of Internet Explorer at the time of disclosure was exposed, and Microsoft shipped fixes as part of its July 2015 security updates. The flaw is listed in CISA's Known Exploited Vulnerabilities catalog (added 2022-03-28), carries a 53.4% EPSS (99th percentile), and related reporting places it among the top vulnerabilities used by exploit kits in 2015-2016.

Do: Apply Microsoft's July 2015 security updates for Internet Explorer per vendor instructions, as required by the CISA KEV catalog, and verify that any legacy Windows systems still running Internet Explorer have received them. Because exploitation typically occurs via drive-by web attacks, retire or fully patch IE on client endpoints and keep endpoint protection enabled to catch exploit-kit delivery. Confirm no workstations remain on unpatched IE builds, since this entry has been in CISA KEV since March 2022 and exploitation probability remains high (EPSS 53.4%).

CVE-2015-5119 is a use-after-free memory-corruption vulnerability (CWE-119) in the ActionScript 3 ByteArray class of Adobe Flash Player. It is triggered when Flash processes crafted ActionScript/SWF content — typically a malicious .swf loaded from a web page, advertisement, email attachment, or document — causing Flash to access already-freed memory in an attacker-controllable way. A successful attack gives the adversary remote code execution in the context of the user running Flash. Anyone with Adobe Flash Player installed was exposed; at disclosure Flash was on the vast majority of internet-connected desktops, and today risk is concentrated in legacy browsers, office/document tooling, industrial or enterprise applications, and other systems where Flash was never removed. Exploitation status: this flaw has long-standing in-the-wild use (related headlines tie the leaked Hacking Team Flash exploit to APT campaigns against Japanese, East Asian, and US Government targets and to top 2016 exploit kits), it is listed in CISA's Known Exploited Vulnerabilities catalog (added 2022-03-03; ransomware use unknown), and EPSS assigns a 99.3% probability of exploitation within 30 days.

Do: Because Flash Player is end-of-life, CISA's required action is to disconnect it rather than patch: audit browsers, document/office tooling, and legacy or industrial applications for Flash dependencies and fully uninstall or disable Flash and any embedded SWF players. If a system must keep Flash temporarily, verify it runs a patched build from 2015 or later (Adobe's July 2015 emergency update, APSB15-16, addressed this flaw) and block untrusted SWF content via browser settings, email gateway, and web filtering. Prioritize cleanup on internet-facing endpoints and users who browse the web or open untrusted email attachments, the typical delivery route for this exploit.

CVE-2016-0189 is a memory corruption flaw (out-of-bounds write, per CWE-787) in Microsoft's JScript 5.8 and VBScript 5.7/5.8 scripting engines, as used in Internet Explorer 9 through 11 and other products that embed those engines. It is triggered remotely when a user is lured into viewing a crafted website that mishandles script, corrupting memory in the browser process. A successful attacker gains arbitrary code execution in the context of the current user (or can crash the browser, causing denial of service), with no authentication required but user interaction needed. Anyone running Internet Explorer 9-11 on Windows, or other products using the affected scripting engines, was exposed. Exploitation is well established: public write-ups document its use in drive-by exploit kit attacks and subsequent 'God Mode' local privilege-escalation variants, it is listed in CISA KEV (added 2022-03-28) with known ransomware use, and EPSS assigns a 94.1% probability of exploitation within 30 days.

Do: Apply the vendor-supplied Microsoft security updates for Internet Explorer and the JScript/VBScript scripting engines per CISA's required action, prioritizing endpoints used for web browsing and email since this is delivered via drive-by website attacks and is known to be used by ransomware operators. Systems that no longer receive updates for IE 9-11 should be migrated to a supported browser or OS. Check your environment against CISA KEV to confirm remediation status.

CVE-2016-1019 is a remotely exploitable flaw in Adobe Flash Player that lets an attacker cause a denial of service or, in the worst case, execute arbitrary code on the victim's system. It is triggered remotely, typically when a user views malicious Flash content delivered through a web browser, an application, or a document that embeds Flash content. A successful attack runs code with the privileges of the logged-on user, making the bug a useful foothold for deploying malware, including ransomware. Anyone still running Adobe Flash Player is potentially affected - the product is end-of-life (support ended December 31, 2020), but it persists on legacy desktops, intranet applications, kiosks, and embedded or industrial systems; the CISA data does not list specific affected version ranges. The flaw is being exploited in the wild: CISA added it to the Known Exploited Vulnerabilities catalog on March 3, 2022, notes known ransomware use, and EPSS assigns a 22.5% probability of exploitation in the next 30 days (98th percentile), though no public proof-of-concept is catalogued.

Do: Per CISA's required action, disconnect or remove any system still running Adobe Flash Player, since the product is end-of-life and receives no further security updates; the bug was patched in Adobe's 2016 updates, so only long-unupdated or embedded Flash installs remain vulnerable. Uninstall Flash from browsers and legacy software and confirm that no internal applications or sites still serve or require SWF content. Because exploitation is tied to ransomware campaigns, prioritize user workstations and any internet-facing host with Flash installed.

CVE-2016-4117 is a critical (CVSS 3.1: 9.8) arbitrary code execution vulnerability in Adobe Flash Player 21.0.0.226 and earlier, in which unspecified vectors in the Flash runtime allow remote attackers to execute arbitrary code. It is triggered by delivering malicious Flash content over a network — for example a crafted SWF loaded by a browser or an application that embeds Flash — and, per its CVSS scoring, requires no privileges or authentication. A successful exploit gives the attacker code execution in the context of the Flash runtime (typically the user's browser process), which public reporting shows was used to deliver espionage tooling and, per CISA, is also known to be used in ransomware campaigns. Anyone running Flash Player 21.0.0.226 or earlier was affected, including users of the flash-player packages shipped for Red Hat Enterprise Linux Desktop, Server (including the RHUI variant) and Workstation, openSUSE, openSUSE Evergreen, and SUSE Linux Enterprise Desktop and the SUSE Linux Enterprise Workstation Extension. The bug was exploited in the wild in May 2016 — related headlines tie it to the BlackOasis APT 'Operation Daybreak' espionage campaign using FinFisher — and it was added to the CISA KEV on 2022-03-03 with known ransomware use and a very high 94.4% EPSS.

Do: Per CISA's required action, Flash Player is end-of-life: remove or disable Flash wherever it is still present and uninstall the flash-player packages on any remaining RHEL, SUSE or openSUSE hosts, especially internet-facing systems. If a legacy system must keep Flash, ensure it runs a release later than 21.0.0.226 (a fixed build from the May 2016 Adobe update or later) and restrict it from untrusted web content.

CVE-2016-7200 is an out-of-bounds write (CWE-787) causing memory corruption in the Chakra JavaScript scripting engine used by Microsoft Edge. A remote attacker triggers it by luring a user to a crafted website, where malicious JavaScript processed by Chakra corrupts memory (the CVSS user-interaction requirement confirms browsing is the attack vector). Successful exploitation allows arbitrary code execution in the context of the logged-on user, or denial of service; confidentiality, integrity, and availability are all rated high. All users of the legacy (Chakra-based) Microsoft Edge browser at the time of the November 2016 disclosure were affected. Exploitation is confirmed in the wild: the flaw is in CISA KEV (added 2022-03-28), public proof-of-concept exploits exist, and it was added to the RIG and Sundown exploit kits, including campaigns delivering Cerber ransomware.

Do: Apply the vendor's cumulative security updates for Microsoft Edge via Windows Update, per CISA's required action, and verify that all Windows 10 endpoints have post-November-2016 Edge updates installed. Note that the current Chromium-based Edge does not use the Chakra engine, so upgrading to a supported Edge/OS build eliminates the vulnerable component. Until patched, limit exposure by steering users away from untrusted websites, since drive-by exploit kits (RIG, Sundown) were actively weaponizing this flaw.

Redirection from an HTTP connection to a "data:" URL assigns the referring site's origin to the "data:" URL in some circumstances. This can result in same-origin violations against a domain if it loads resources from malicious sites. Cross-origin setting of cookies has been demonstrated without the ability to read them. Note: This issue only affects Firefox 49 and 50. This vulnerability affects Firefox < 50.0.1.

CVE-2017-0037 is a type confusion flaw (CWE-843) in Microsoft Internet Explorer 10 and 11 and Microsoft Edge, located in the Layout::MultiColumnBoxBuilder::HandleColumnBreakOnColumnSpanningElement function of mshtml.dll. It is triggered when the browser processes a crafted Cascading Style Sheets token sequence combined with JavaScript that operates on a TH (table header) element, typically delivered via a malicious or compromised web page. An attacker who successfully exploits it can execute arbitrary code in the context of the browser process. Any user running the affected legacy Microsoft browsers is exposed, which historically meant most Windows desktops. The flaw was publicly disclosed via Google Project Zero after a 90-day deadline passed, public proof-of-concept exploits are available, and it is listed in CISA's Known Exploited Vulnerabilities catalog (added 2022-03-28), confirming in-the-wild exploitation.

Do: Apply Microsoft security updates per vendor instructions (the flaw was addressed in Microsoft's March 2017 Patch Tuesday, which followed the Project Zero disclosure), prioritizing systems in CISA KEV scope. Inventory for any hosts still running IE 10/11 or legacy (pre-Chromium) Edge and retire or isolate them, as legacy Microsoft browsers are end-of-life. As an interim mitigation, avoid using affected browsers for untrusted web content, since exploitation requires rendering attacker-crafted CSS/JavaScript.

An issue was discovered in the Cisco WebEx Extension before 1.0.7 on Google Chrome, the ActiveTouch General Plugin Container before 106 on Mozilla Firefox, the GpcContainer Class ActiveX control plugin before 10031.6.2017.0126 on Internet Explorer, and the Download Manager ActiveX control plugin before 2.1.0.10 on Internet Explorer. A vulnerability in these Cisco WebEx browser extensions could allow an unauthenticated, remote attacker to execute arbitrary code with the privileges of the affected browser on an affected system. This vulnerability affects the browser extensions for Cisco WebEx Meetings Server and Cisco WebEx Centers (Meeting Center, Event Center, Training Center, and Support Center) when they are running on Microsoft Windows. The vulnerability is a design defect in an application programing interface (API) response parser within the extension. An attacker that can convince an affected user to visit an attacker-controlled web page or follow an attacker-supplied link with an affected browser could exploit the vulnerability. If successful, the attacker could execute arbitrary code with the privileges of the affected browser.

JIT code allocation can allow for a bypass of ASLR and DEP protections leading to potential memory corruption attacks. This vulnerability affects Thunderbird < 45.7, Firefox ESR < 45.7, and Firefox < 51.