Malicious PDF — malware analysis report

Static analysis result for SHA-256 55be5b3e7de07ce2…

MALICIOUS

PDF

80.9 KB Created: 2021-09-08 18:15:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: dd21979c22b42975d2082199cf474327 SHA-1: a5580bdbb4979d7bbfe5540d7218a253ee2dc5fc SHA-256: 55be5b3e7de07ce25e0fe8f4de9dc24cbbd6c2e3e3d08c77ea6e96f23c17e735
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting it's designed to redirect users to malicious sites. The presence of numerous unknown URLs further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://inprovitargentina.com/ckfinder/userfiles/files/juxuma.pdf In PDF document text
    • http://kyochonbuenapark.iorderfoods.com/uploads/files/voxebokorigagafifimef.pdfIn PDF document text
    • http://www.fdconsult.qa/public/uploads/cms_files/piletufowuzuwusexavoze.pdfIn PDF document text
    • http://okna-kurska.ru/page_edit/_samples/userfiles/files/zewisi.pdfIn PDF document text
    • http://healingtown.org/userData/board/file/79604118730.pdfIn PDF document text
    • https://k85shj16h-561lt.com/contents/files/junudixizokakowugunonud.pdfIn PDF document text
    • http://rs-entp.com/upload/file/rikif.pdfIn PDF document text
    • https://pre-www.bridge-college.com/uploaded/ckeditor/files/fasozezetuwanurujalotutij.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/2c3505c9e5d8aecb90af449cd811ad5b/58109164922.pdfIn PDF document text
    • http://dentalweek.eu/userfiles/files/69581472255.pdfIn PDF document text
    • http://bayanairag.com/uploads/userfiles/files/puzokiwivezogow.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613357f0aa533---vemavuka.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/lerigogidu.pdfIn PDF document text
    • https://linhngapt.vn/upload/files/71661972126.pdfIn PDF document text
    • http://www.boldino-hotel.com/ckfinder/userfiles/files/vonavuvukosexijoxa.pdfIn PDF document text
    • http://aucontecnologia.com/userfiles/files/lanofixadagik.pdfIn PDF document text
    • http://d-innovation.com/upload/files/52613074862.pdfIn PDF document text
    • http://cassotech.nl/site/data/ws/files/fasimabisuvaxujugu.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/16136eb208c44e---natexetepiviwabufolev.pdfIn PDF document text
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/825bd13c418dc601cdadff1aa7ff0196/pezuvepisibozurup.pdfIn PDF document text
    • http://rentappli.com/tinymce/jscripts/tiny_mce/plugins/phpimage/phpimage/upload/images/file/81026412677.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136a463822c5---24471887108.pdfIn PDF document text
    • http://zechnerbau.at/images/content/files/94255628908.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/89733087908.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=completing+story+pdfPDF 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_off0000d664.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD664 17964 bytes
SHA-256: 95aea30523858a5ee34ad282b372c4dd9a3a4ab08bd9841918b7063077d59fd0
font_01_sfnt_off00010536.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10536 10824 bytes
SHA-256: f735532f42f17c480f69d6b607ff47f6f542a2b5eb1da77d0f71da68bbf76d8a
font_02_sfnt_off00011dec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DEC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1