Malicious PDF — malware analysis report

Static analysis result for SHA-256 6888149b0ff3550f…

MALICIOUS

PDF

85.8 KB Created: 2021-06-25 20:45:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 76a968ef4800c374d9c56da635ccc73d SHA-1: 4fbf9ef93af52923d87b5eaa73ecf106c24b4273 SHA-256: 6888149b0ff3550f0c28a4e7af0387c2f8a70eaa2333c09d09dbd7e3cc020e36
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample is a PDF document containing embedded JavaScript and a link farm pointing to multiple compromised WordPress sites. These links likely serve as a lure to download additional malicious payloads, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/65024feea9ae8ea460639a1a28fe93d7/75628186826.pdf In PDF document text
    • http://classconnbio.com/img-jacson/files/nifakufufomofegiretikike.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/v7jca4emoi0hb9sj0v2ib2lhe3/18744324405.pdfIn PDF document text
    • https://avgdesign.com/userfiles/file/65355130342.pdfIn PDF document text
    • http://micronforgacsolo.hu/UserFiles/file/55882134646.pdfIn PDF document text
    • http://urbanconstructions.org/images/uploadedimages/file/46583414496.pdfIn PDF document text
    • https://energooptima.hu/upload/File/84657607541.pdfIn PDF document text
    • https://space1500.com/wp-content/plugins/super-forms/uploads/php/files/60a74281f027193faa191bc77fbfb313/devemoxexap.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082d1d9b9cc2---11534746270.pdfIn PDF document text
    • http://aviapartner.biz/js/ckfinder/userfiles/files/lelavivekawomovibo.pdfIn PDF document text
    • https://xehowo24h.com/images/ckeditor/files/78430885490.pdfIn PDF document text
    • https://edoxmarketing.com/wp-content/plugins/super-forms/uploads/php/files/l4olr1pfcer4okq6ti5l11bg2u/gulerul.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608cb8ca3b150---8372163572.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1607d8f2c23d73---lomezutonemubosupokonowur.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/sezatasomuzumilupopa.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/qgma6pfe1gjg45b4kkn5cael9n/tosovufatazaruxedafa.pdfIn PDF document text
    • http://namngonviet.vn/user-/files/nixepovisikemutisa.pdfIn PDF document text
    • https://travelworld.ro/userfiles/file/14679936907.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dbe3c6f979---lalofutuxutavu.pdfIn PDF document text
    • http://vieclamquantri.net/upload/files/75625802673.pdfIn PDF document text
    • http://mldinsaat.com/image/files/gewopatigirofexozugebij.pdfIn PDF document text
    • https://shayangroup.net/wp-content/plugins/super-forms/uploads/php/files/2f9aaa5f22c23cc87b6493ec66fce62c/20265583856.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/160780707074ac---fojodepexufafekoxawuzi.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/jozepegadatomusugajenaz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=oppo+a37+android+7+updatePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE54 16676 bytes
SHA-256: 6d21cb91c013436e7b0684f576cd0e020cfe5be58c6086a84397bfddc7860235
font_01_sfnt_off000119ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000131c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131C5 10516 bytes
SHA-256: 75d2e1118db614a69f4166d7f97db16dca0e0279d4f9d0bc0f62bf60f48d10e1