{"id":22490,"date":"2023-07-17T16:11:04","date_gmt":"2023-07-18T00:11:04","guid":{"rendered":"http:\/\/www.palada.net\/index.php\/2023\/07\/17\/news-16220\/"},"modified":"2023-07-17T16:11:04","modified_gmt":"2023-07-18T00:11:04","slug":"news-16220","status":"publish","type":"post","link":"https:\/\/www.palada.net\/index.php\/2023\/07\/17\/news-16220\/","title":{"rendered":"Act now! In-the-wild Zimbra vulnerability needs a workaround"},"content":{"rendered":"<p>Security experts are warning Zimbra users that a vulnerability for which there is no patch is being actively exploited in the wild. In a <a href=\"https:\/\/info.zimbra.com\/security-update-zimbra-collaboration-suite-version-8.8.15-important\" target=\"_blank\" rel=\"nofollow\">security update<\/a> about the vulnerability, the company offered a temporary workaround which users can apply while waiting for a patch to be created.<\/p>\n<p>Zimbra is an open source webmail application used for messaging and collaboration. The vulnerability, which could impact the confidentiality and integrity of users&#8217; data, exists in Zimbra Collaboration Suite Version 8.8.15.<\/p>\n<p>Zimbra is widely used across different industries and government organizations. We reported about a <a href=\"https:\/\/www.malwarebytes.com\/blog\/news\/2022\/02\/threat-actor-steals-email-with-zimbra-zero-day\">cross-site scripting (XSS) zero-day vulnerability in the Zimbra email platform<\/a> back in February 2022. At the time, Zimbra claimed there were 200,000 businesses, and over a thousand government and financial institutions, using its software. Thousands of Zimbra mail servers were backdoored in a large scale attack exploiting that vulnerability.<\/p>\n<p>In our <a href=\"https:\/\/www.malwarebytes.com\/blog\/threat-intelligence\/2023\/06\/ransomware-review-june-2023\">June 2023 ransomware review<\/a> we noted how the MalasLocker ransomware group had targeted vulnerabilities in Zimbra servers, including <a href=\"https:\/\/cve.mitre.org\/cgi-bin\/cvename.cgi?name=CVE-2022-24682\" target=\"_blank\" rel=\"nofollow\">CVE-2022-24682<\/a>, to enable remote code execution (RCE). This resulted in MalasLocker taking first place on the list of known attacks over the month of May 2023, displacing perennial top-spot holder LockBit.<\/p>\n<figure style=\"text-align: center;\"><figcaption><img decoding=\"async\" src=\"https:\/\/www.malwarebytes.com\/blog\/news\/2023\/07\/easset_upload_file7562_272657_e.jpg\" alt=\"May 2023 chart\" width=\"700\" \/><\/figcaption><figcaption><em>Known ransomware attacks by gang, May 2023<\/em><\/figcaption><\/figure>\n<p>Since Zimbra mentions no further details, it is hard to determine what the exact problem is. Although the proposed fix (down below under Mitigation) suggest that there may be a problem which can be exploited by utilizing specially crafted XML files. By using the <code>fn:escapeXml()<\/code> function, which escapes characters that can be interpreted as XML markup, users will manually add input sanitization.<\/p>\n<p>Zimbra makes no mention of active exploitation, but Google researcher Maddie Stone tweeted about another researcher in the Google Threat Analysis Group noticing the vulnerability being used in-the-wild in a targeted attack.<\/p>\n<blockquote class=\"twitter-tweet\">\n<p dir=\"ltr\" lang=\"en\">.<a href=\"https:\/\/twitter.com\/_clem1?ref_src=twsrc%5Etfw\">@_clem1<\/a> discovered this being used in-the-wild in a targeted attack. Thank you to <a href=\"https:\/\/twitter.com\/Zimbra?ref_src=twsrc%5Etfw\">@Zimbra<\/a> for publishing this advisory and mitigation advice! If you run Zimbra Collaboration Suite, please go manually apply the fix! <a href=\"https:\/\/twitter.com\/hashtag\/itw0days?src=hash&amp;ref_src=twsrc%5Etfw\">#itw0days<\/a> <a href=\"https:\/\/t.co\/lqwt0kOFWA\">https:\/\/t.co\/lqwt0kOFWA<\/a><\/p>\n<p> &mdash; Maddie Stone (@maddiestone) <a href=\"https:\/\/twitter.com\/maddiestone\/status\/1679542322772721664?ref_src=twsrc%5Etfw\">July 13, 2023<\/a><\/p><\/blockquote>\n<p> <script async=\"\" src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script> Earlier vulnerabilities in Zimbra allowed cybercriminals to <a href=\"https:\/\/www.malwarebytes.com\/blog\/news\/2022\/02\/threat-actor-steals-email-with-zimbra-zero-day\">steal emails in targeted attacks<\/a> against organizations in the European government and media sectors.<\/p>\n<h2>Mitigation<\/h2>\n<p>The Zimbra security update suggests you apply the follow fix manually on all of your mailbox nodes:<\/p>\n<ol>\n<ol>\n<li>Take a backup of the file <em>\/opt\/zimbra\/jetty\/webapps\/zimbra\/m\/momoveto<\/em><\/li>\n<li>Then open to edit the active file and go to line number 40<\/li>\n<li>Change <br \/><code>&lt;input name=\"st\" type=\"hidden\" value=\"${param.st}\"\/&gt;<\/code><br \/>to <br \/><code>&lt;input name=\"st\" type=\"hidden\" value=\"${fn:escapeXml(param.st)}\"\/&gt;<\/code><\/li>\n<\/ol>\n<\/ol>\n<p>Zimbra notes that a service restart is not required so you can do it without any downtime.<\/p>\n<p>We will keep you posted when a patch is made available and in case there are other developments around this bug.<\/p>\n<hr \/>\n<p><strong>We don&rsquo;t just report on vulnerabilities&mdash;we identify them, and prioritize action.<\/strong><\/p>\n<p>Cybersecurity risks should never spread beyond a headline. Keep vulnerabilities in tow by using <a href=\"https:\/\/www.malwarebytes.com\/business\/vulnerability-patch-management\">Malwarebytes Vulnerability and Patch Management<\/a>.<\/p>\n<p><a href=\"https:\/\/www.malwarebytes.com\/blog\/news\/2023\/07\/act-now-unpatched-zimbra-vulnerability-is-actively-exploited\" target=\"bwo\" >https:\/\/blog.malwarebytes.com\/feed\/<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<table cellpadding=\"10\">\n<tr>\n<td valign=\"top\" align=\"left\">\n<p>Categories: <a href=\"https:\/\/www.malwarebytes.com\/blog\/category\/exploits-and-vulnerabilities\" rel=\"category tag\">Exploits and vulnerabilities<\/a><\/p>\n<p>Categories: <a href=\"https:\/\/www.malwarebytes.com\/blog\/category\/news\" rel=\"category tag\">News<\/a><\/p>\n<p>Tags: Zimbra<\/p>\n<p>Tags:  MalasLocker<\/p>\n<p>Tags:  vulnerability<\/p>\n<p>Tags:  Google<\/p>\n<p>Tags:  actively exploited<\/p>\n<p>Tags:  fn:escapeXml<\/p>\n<p>Security experts are warning Zimbra users that a vulnerability for which there is no patch is being actively exploited in the wild. <\/p>\n<table width=\"100%\">\n<tr>\n<td align=\"right\">\n<p><b>(<a href=\"https:\/\/www.malwarebytes.com\/blog\/news\/2023\/07\/act-now-unpatched-zimbra-vulnerability-is-actively-exploited\" title=\"Act now! In-the-wild Zimbra vulnerability needs a workaround\">Read more&#8230;<\/a>)<\/b><\/p>\n<\/td>\n<\/tr>\n<\/table>\n<\/td>\n<\/tr>\n<\/table>\n<p>The post <a rel=\"nofollow\" href=\"https:\/\/www.malwarebytes.com\/blog\/news\/2023\/07\/act-now-unpatched-zimbra-vulnerability-is-actively-exploited\">Act now! In-the-wild Zimbra vulnerability needs a workaround<\/a> appeared first on <a rel=\"nofollow\" href=\"https:\/\/www.malwarebytes.com\">Malwarebytes Labs<\/a>.<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"colormag_page_container_layout":"default_layout","colormag_page_sidebar_layout":"default_layout","footnotes":""},"categories":[10488,10378],"tags":[27318,22783,29809,1670,29808,32,10467,24840],"class_list":["post-22490","post","type-post","status-publish","format-standard","hentry","category-malwarebytes","category-security","tag-actively-exploited","tag-exploits-and-vulnerabilities","tag-fnescapexml","tag-google","tag-malaslocker","tag-news","tag-vulnerability","tag-zimbra"],"_links":{"self":[{"href":"https:\/\/www.palada.net\/index.php\/wp-json\/wp\/v2\/posts\/22490","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.palada.net\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.palada.net\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.palada.net\/index.php\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.palada.net\/index.php\/wp-json\/wp\/v2\/comments?post=22490"}],"version-history":[{"count":0,"href":"https:\/\/www.palada.net\/index.php\/wp-json\/wp\/v2\/posts\/22490\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.palada.net\/index.php\/wp-json\/wp\/v2\/media?parent=22490"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.palada.net\/index.php\/wp-json\/wp\/v2\/categories?post=22490"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.palada.net\/index.php\/wp-json\/wp\/v2\/tags?post=22490"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}