Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c7918727cd7d5f5…

MALICIOUS

PDF

68.5 KB Created: 2021-09-14 08:53:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c203e696f4f3f00958ac6d3f4cfe3e78 SHA-1: d6c871815f88ea14169ba5805ba39fa2946ce9b6 SHA-256: 7c7918727cd7d5f542f117fac0f528a78f350574f1af710962314f85f05c844c
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing or trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS platforms. The presence of numerous URLs, including those with UTM parameters suggesting tracking, reinforces the phishing or malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://krisoc.ru/uplcv?utm_term=big+big+baller+io+game PDF link annotation
    • https://mvpartners.be/images/uploadedimages/file/vidurugejodedizam.pdfIn PDF document text
    • http://yenidenyuzlendirme.com/ckfinder/userfiles/files/fenomapaxapejuse.pdfIn PDF document text
    • https://reazfarah.com/ckfinder/userfiles/files/milizigeno.pdfIn PDF document text
    • http://suvenirzp.com/uploads/files/43448776113.pdfIn PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/35507669956.pdfIn PDF document text
    • http://permanentnimakeup-brno.cz/userfiles/files/wezopi.pdfIn PDF document text
    • http://bioaec.com/userfiles/files/tadox.pdfIn PDF document text
    • https://adium.ru/userfiles/file/vepiwekawojowudaxafef.pdfIn PDF document text
    • http://rulada.by/upload/editor/files/54814818747.pdfIn PDF document text
    • https://cancelaria.pl/galeria/file/17617108814.pdfIn PDF document text
    • http://sarljarry.com/userfiles/file/gibelokeridodebafuperu.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1613581119288b---zirilubutiraz.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/5c5c6b341322478149529bf84d139003/91330074273.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/2f8ab082944c3401b7b05649ee968fcf/degukiwusararure.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/t9j2rckpn0edibbshh1clttgo1/pedibemelaxoxufek.pdfIn PDF document text
    • https://pcetravel.com/files/file/62287671438.pdfIn PDF document text
    • http://babyindex.nl/images/uploads/gabajopazojakega.pdfIn PDF document text
    • http://ardechetendancebrut.fr/userfiles/ardechetendancebrut.fr/file/daxopeni.pdfIn PDF document text
    • http://dbcasagayathottam.org/assets/uploads/cms_images/files/98836170009.pdfIn PDF document text
    • https://stockbauer.hu/uploads/file/53331703227.pdfIn PDF document text
    • https://digireg.it/upload/bexokepozufabutof.pdfIn PDF document text
    • http://campbellelectronics.com/uploads/liboxot.pdfIn PDF document text
    • http://digitalqwerty.com/ckfinder/userfiles/files/jifebap.pdfIn PDF document text
    • 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_off0000af5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF5A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c771.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC771 10276 bytes
SHA-256: 1afc2309b7edb5fe1bf712eb5ac3472825c0fa4f74f2b4bd420fc664258c3faf
font_02_sfnt_off0000de8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE8C 14944 bytes
SHA-256: 72458ef896c75f03c06575d16b3e8c1e05c689e1b61dd6831f0f7fdc75a77d3a