Malicious PDF — malware analysis report

Static analysis result for SHA-256 66ef541bceb8e3aa…

MALICIOUS

PDF

87.1 KB Created: 2021-06-27 23:31:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 599bf4fc070f2840f13db50774912ee6 SHA-1: 3400c4b777579c5ed2414072aafc5e1ad0c06393 SHA-256: 66ef541bceb8e3aa9e323c113a9409702ac6797ba2412e568e99ac8fa17b1883
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm with numerous URLs pointing to compromised CMS upload storage, indicating an attempt to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple external URIs and the nature of the links suggest this file is part of a larger distribution effort, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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 http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc1f3ebcf32---nekazozujujuguzaxovop.pdf In PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a443bf492a8---91268526603.pdfIn PDF document text
    • https://englewoodgrassfarm.com/wp-content/plugins/super-forms/uploads/php/files/ee22da88ae44c81c9ea5c7f7deba3781/55311311604.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aa0a0f37e13---morufajogajoxebujez.pdfIn PDF document text
    • http://skybuildinfraprojects.com/uploads/67329755648.pdfIn PDF document text
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/0d2b82d67944e701127e230e1a9fb444/nafukovovewuderadu.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082c3cabbedc---kotenaborofepel.pdfIn PDF document text
    • http://gtshotel.it/images/file/20406544736.pdfIn PDF document text
    • https://whatproperty.ng/ckfinder/userfiles/files/vodega.pdfIn PDF document text
    • http://nhadep30giay.com/uploads/image/files/3848723330.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/c145611aac88ca1e133141c1ec109eec/notowofowafoti.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608a515c477b2---koliwazisinukinafelidepoz.pdfIn PDF document text
    • http://jrmhandling.nl/upload/file/veburavutamutewipizi.pdfIn PDF document text
    • http://elmbbq.com/uploads/files/wiselolazefukipuxujunorub.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/0t8hs80i65bd0opv774cbtdmql/86486175789.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/simadapa.pdfIn PDF document text
    • https://warungmimpishio.com/contents//files/36909745659.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1608402510ea57---zaxebiv.pdfIn PDF document text
    • http://group-anons.ru/userfiles/files/56050988415.pdfIn PDF document text
    • http://donkaew-furniture.com/ckfinder/userfiles/files/gazimigave.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1607395430ce95---likoxafubizo.pdfIn PDF document text
    • http://patronusalapitvany.hu/public_html/upload/31109849683.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/22455493059.pdfIn PDF document text
    • https://augsburger-dartliga.de/uploads/file/lotikawog.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=farming+simulator+20+android+download+freePDF 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_off0000e720.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE720 22764 bytes
SHA-256: 238ae9ecf001afbefc5e1240cf619a0803bd3e49e84b5f68a8e65d9775a23176
font_01_sfnt_off00011d55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D55 11104 bytes
SHA-256: 59e08df3053db8c64856b319432a97d5fbec168a359b3b89fefd7cd8fdc68836
font_02_sfnt_off0001371d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1371D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1