Malicious PDF — malware analysis report

Static analysis result for SHA-256 87e7de542159472f…

MALICIOUS

PDF

84.9 KB Created: 2021-09-23 01:49:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 339fa12ada9004e05bbbaaecdd1fd134 SHA-1: b5efdf625fd8dfc332b58b06153a284697e1adba SHA-256: 87e7de542159472f15f76d62b6bfc34bd2bafff6e413d3f23d582d1b73995d1e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to obscure the ultimate destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL analysis point to a common tactic of using link farms to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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.
  • 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://polyalpan.hu/_user/file/62960035326.pdf In PDF document text
    • https://liantoong.com/archive/upload/files/gejoxel.pdfIn PDF document text
    • https://5of7edwardstreet.com/assets/media/files/zabojinilepozuf.pdfIn PDF document text
    • http://sportsgarten.com/editorData/file/xopidotagodirelemekevuxi.pdfIn PDF document text
    • https://feniks9.ru/ckfinder/userfiles/files/varevedu.pdfIn PDF document text
    • https://xpress2.eu/ckfinder/userfiles/files/95611451986.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/a1e58b132f464e2f67356779ec344284/28781211980.pdfIn PDF document text
    • https://selapro.com.au/application/third_party/ckfinder/userfiles/files/16401313746.pdfIn PDF document text
    • http://taiwan-casters.com/userfiles/file/68613016759.pdfIn PDF document text
    • http://klhl.com/userfiles/file/50901600122.pdfIn PDF document text
    • https://atamergranit.com/userfiles/file/65148232548.pdfIn PDF document text
    • http://dijladentalcenter-qa.com/userfiles/file/xuxaxikuwis.pdfIn PDF document text
    • http://severstroysnab.ru/userfiles/file/mutujap.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/312bb53860c05101258c1ba07076dd5b/43364376884.pdfIn PDF document text
    • https://laznia-radom.pl/userfiles/file/67216691165.pdfIn PDF document text
    • https://hotelharmika.com/assets/userfiles/files/66800651763.pdfIn PDF document text
    • http://alwaditrading.com/userfiles/files/80040537627.pdfIn PDF document text
    • https://enilubricantvn.hoakhanh.vn/uploads/image/files/7340489008.pdfIn PDF document text
    • http://karmakonnect.org/DrumiBhatt/karmakonnect.org/Final/ckeditorimage/files/zawireje.pdfIn PDF document text
    • https://intersat.lv/files/file/wivigunikalufegivom.pdfIn PDF document text
    • http://ghettaetamionarchitetti.it/userfiles/files/94738394778.pdfIn PDF document text
    • https://eijo.in/ckfinder/userfiles/files/41972427216.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/161403d8d7c4f8---jijenefakav.pdfIn PDF document text
    • https://marathonroller.com/userfiles/files/42024730359.pdfIn PDF document text
    • http://evevoyance.fr/adh/.-/file/76749499217.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=aquarium+live+wallpaper+apkPDF 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_off0000dbe7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBE7 22480 bytes
SHA-256: d5aa4f1272cab30c05f1570c33738e952646ed3c6fcc5e731724681772249fe5
font_01_sfnt_off000116ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116EE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012f05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F05 10392 bytes
SHA-256: aad0d3825bcc59dd9bbc55d320fabd8ba0873427136cde54961cf84b2f20b0b8