Malicious PDF — malware analysis report

Static analysis result for SHA-256 e2c0444b9a958316…

MALICIOUS

PDF

85.9 KB Created: 2021-09-23 06:49:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5d5371a759a2d8686ca668989bfe7ad5 SHA-1: 92644c8f7b7e5e4b823174d306790abf5effc75c SHA-256: e2c0444b9a9583165c38711a03a478b807f9c2c85909b6dd0071f5a59623e822
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS platforms. The document body is heavily obfuscated and appears to be non-readable content generated by wkhtmltopdf, suggesting the primary function is to host these malicious links.

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://wastran.ru/uplcv?utm_term=cw+fetter+applied+hydrogeology+pdf PDF link annotation
    • https://hobbes-group.com/upload/files/73256157882.pdfIn PDF document text
    • https://motty-etai-sharon.com/files/files/35361194234.pdfIn PDF document text
    • https://hondamienbac.vn/userfiles/file/82883352896.pdfIn PDF document text
    • http://austria-ex.com/images/blog/file/5220050011.pdfIn PDF document text
    • http://degeninhotel.ru/admin/ckfinder/userfiles/files/38600203083.pdfIn PDF document text
    • https://blokhol.com/upload/files/91818478259.pdfIn PDF document text
    • https://fetogram.ir/images/upload/files/kajazotivogobebopukamabib.pdfIn PDF document text
    • http://myrbacken.se/login/ckfinder/userfiles/files/mivozevapegakikar.pdfIn PDF document text
    • http://lapmaymn.samdigroup.vn/app/webroot/upload/files/10703171133.pdfIn PDF document text
    • https://sapsda.org/SapmaUserfiles/file/32073047686.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/rakanebegadezololonu.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/pfu02b6jc01r3m84h2ai6ol59j/pimovagatudapi.pdfIn PDF document text
    • http://www.egymast-segito.hu/uploaded/fck/file/2069550599.pdfIn PDF document text
    • https://zoorichi.com/temp/fckeditor/file/moxegifufukujixujof.pdfIn PDF document text
    • https://thefertilizergranulators.com/d/files/50852997877.pdfIn PDF document text
    • http://schuetzenfest-hemeringen.de/ablage/userfiles/files/nanemidopavew.pdfIn PDF document text
    • https://www.champagne-cornevin.fr/ckfinder/userfiles/files/62196993051.pdfIn PDF document text
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16136faa31195a---xitewa.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/t22mka92ns5ie8mkfadfoodup5/71296254615.pdfIn PDF document text
    • http://baove24h.org/upload/files/jejibugilavedenanelak.pdfIn PDF document text
    • http://reklama-v-sochi.com/ckfinder/userfiles/files/10503201706.pdfIn PDF document text
    • http://angelofthewinds.net/ckfinder/userfiles/files/tufokawalazafelexow.pdfIn PDF document text
    • http://dvg.asia/ckfinder/uploadfiles/files/lezujopa.pdfIn PDF document text
    • http://majorpropertygroup.com/userfiles/files/49856298616.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_off0000e833.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE833 10736 bytes
SHA-256: 375516a86895f747d4a4f05e7ea95963f97e07bb9f2e295400e8a9c687df3dc0
font_01_sfnt_off000100d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100D8 18708 bytes
SHA-256: 6de444cb0a32ca050e3374f026b91ac961096ca3d95c15c53652b3a987abda01
font_02_sfnt_off000131b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131B8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1