Malicious PDF — malware analysis report

Static analysis result for SHA-256 31c36754252845e7…

MALICIOUS

PDF

79.2 KB Created: 2021-06-29 09:04:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0903dfe189d04bbc15c0d03dd2bfb418 SHA-1: de422fa363e78930671630a90372a535192ba8e8 SHA-256: 31c36754252845e7d8a39d45c51b8ba2c0ab3c9a230a4f4d734fa727f368e3d4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of external URIs and links to compromised WordPress upload storage, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the links and the PDF structure point towards an attempt to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://crysiq.ru/uplcv?utm_term=packard+bell+easynote+disassembly+manual
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/vjuveo3964k0hlbdtv3cvh60u5/1768651955.pdf
    • http://dinskayarealty.ru/media/file/19993585074.pdf
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608ec40d512d1---5127644335.pdf
    • https://charlesstreetvideo.com/userfiles/file/guxipopifutalemo.pdf
    • http://ozkayalartrans.com/userfiles/file/dulebisime.pdf
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160b9a468ec2da---65001986405.pdf
    • http://amsaneeraus.fi/userfiles/files/gejaziwadalatu.pdf
    • http://nordicaluminium.ru/userfiles/file/varupon.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/3a4c311cae9e0bead04027a411e64c20/tojitewagokotorovepive.pdf
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae9c79cd429---7539969649.pdf
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16090f44360799---sipadepawexuzugavim.pdf
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/f7oi7md2slr4ej1eauh7qn8u6i/99671753651.pdf
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/0cb67c08050c2d249262527a7ba5e375/85609441621.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160890b26924ee---tiforadejawimede.pdf
    • http://davcpundri.com/css/file/kibupakomenepotijuvajur.pdf
    • http://hoondb.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081aeeb6e2a0---34305536385.pdf
    • http://kondicionery-krasnogorsk.ru/upload_picture/file/99679845543.pdf
    • https://www.mii.net/wp-content/plugins/super-forms/uploads/php/files/5cbad3c9cc39bf6c5fa74808a1472ddb/93474229572.pdf
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/d5fd4c8eade06399d7e48c3d2ac7c6c5/modoporevisiwagaramad.pdf
    • https://jjcfurnituremaker.com/userfiles/files/64056783784.pdf
    • http://guides2alpes.fr/uploads/file/54608594912.pdf
    • http://biosafety.biz/ckfinder/userfiles/files/48181542301.pdf
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b342e6df6---kaxunesexukilo.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/10e58942f65e6919b75b47bad9bd18a8/jufobavo.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d3e3.bin
b9a5ac24f967717607effee1bb443754015fc3c4e63abb0444f45b995173534c
pdf-font-stream PDF embedded font (sfnt) at offset 0xD3E3 10976 bytes
font_01_sfnt_off0000ed6d.bin
cfb8811af73ce920e2314782d20422a53bd461c0b58d5b410ed3f5c4d2fabe22
pdf-font-stream PDF embedded font (sfnt) at offset 0xED6D 16236 bytes
font_02_sfnt_off0001177b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1177B 16792 bytes