Malicious PDF — malware analysis report

Static analysis result for SHA-256 083a75e37a6c91c5…

MALICIOUS

PDF

80.9 KB Created: 2021-09-19 06:11:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8bac4a2d01cc5adb40c7fccaff9dbd91 SHA-1: ee3390c3a0ac0b54ecd147f00731f610ead40b6a SHA-256: 083a75e37a6c91c58a8b75f5c17f30e4ce81ad3ea04f076a9cb281336363bac8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised websites, a common tactic for distributing malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The presence of numerous links on potentially compromised CMS upload directories suggests an attempt to obscure the true origin of the malicious payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 http://victoryelectricalsupply.com/ckfinder/userfiles/files/67428987100.pdf In PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/huecdeeg69kels5ikjabmvnk0t/26343610699.pdfIn PDF document text
    • http://paillasse.hu/userfiles/file/tatuwaxamatokukoge.pdfIn PDF document text
    • http://portaldeaquidauana.com.br/ckfinder/userfiles/files/jijutenidapetekosodoz.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-9-14/20210914025231920686.pdfIn PDF document text
    • http://tahi.hu/ckfinder/userfiles/files/96021940408.pdfIn PDF document text
    • http://dgone.kr/userfiles/file/20210919030133.pdfIn PDF document text
    • http://agt.es/files/galeria2/files/99175849309.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/d9adae73f5ee6deb7f8e0b5da1504f2d/55938474642.pdfIn PDF document text
    • http://jmk.kr/ckfinder/userfiles/files/30724594736.pdfIn PDF document text
    • http://grandp.ru/userfiles/file/fipixanonibetitoxovofoz.pdfIn PDF document text
    • https://karaari.leaddeehub.com/userfiles/files/jojilesulenupival.pdfIn PDF document text
    • https://btcauction.vn/hinhanh/file/32638278774.pdfIn PDF document text
    • http://huiking.cn/uploads/file/171037274448.pdfIn PDF document text
    • http://poliinc.com/upload/files/vuxalefolitobewasuno.pdfIn PDF document text
    • http://clickvay.com/upload/files/ropilinagozafemoz.pdfIn PDF document text
    • http://nutronicltd.com/userfiles/file/vepisusanapel.pdfIn PDF document text
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/aa9f3162a8278338542081d756c232d8/pofod.pdfIn PDF document text
    • https://www.sophrologue-nimes.fr/upload/news/files/mifemo.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/161314e1adc59b---votuvesoxirire.pdfIn PDF document text
    • http://tieulongcopro.com/luutru/files/19923997365.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=timeline+of+homosapien+evolutionPDF 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_off0000d809.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD809 17748 bytes
SHA-256: 18c938048fa8f2f7e1d11c9c3449c2f576f904506b1a5b618faba73a77c94924
font_01_sfnt_off000105ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011dc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DC5 10652 bytes
SHA-256: 45070d324d73b4f78bf599aa3af4bb1b2395ca2a5e84cff24384168a89b6d45f