Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fdc030c7b0d9c8b…

MALICIOUS

PDF

75.2 KB Created: 2021-09-16 15:09:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: eefda56d78e48aa91fed909b05ea48bf SHA-1: 89cd42b638d7f8442d26b1ae58dd242c3737b1d1 SHA-256: 8fdc030c7b0d9c8bc1f972a80166b3301dfa60a2f0987b681e7f398e255f610c
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to other PDF files hosted on various domains, many of which appear to be compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple 'link farm' heuristics reinforces the attack pattern of directing users to external, potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://chcial.ru/uplcv?utm_term=weixin+apk+download PDF link annotation
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/111cbd5d5c53707cd0355f5eb432bd75/vegadawisetigokoxe.pdfIn PDF document text
    • https://aradovan.com/userfiles/file/wolopataxazabirivin.pdfIn PDF document text
    • http://stylekd.ru/files/91843890786.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/p5uj7677n75ij0pt2t5ojlodhf/towotibune.pdfIn PDF document text
    • https://netiko.ge/img/Data/file/20380714359.pdfIn PDF document text
    • http://pluimveebeurs.com/userfiles/file/mimolozub.pdfIn PDF document text
    • http://fujieshubao.com/zk/UploadFile/file/2021091104002773499.pdfIn PDF document text
    • http://sweepinstyle.com/userfiles/file/66424230310.pdfIn PDF document text
    • http://thebrownbag.vn/upload/files/loziwuxaxiposerud.pdfIn PDF document text
    • https://chameleoncoupons.com/adgprocessing/uploads/files/vipujuzinozigonoxo.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613730c0a6a2e---27224479681.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613507012f5b3---vibogujedabetuwiti.pdfIn PDF document text
    • http://vytvarnyobchod.cz/UserFiles/File/77184560664.pdfIn PDF document text
    • http://mail-ex.net/userfiles/file/5173213685.pdfIn PDF document text
    • http://contextuae.com/resimler/files/89263376537.pdfIn PDF document text
    • http://sms-dk.com/FileData/ckfinder/files/20210907_D08EC6975F7B1E3F.pdfIn PDF document text
    • http://namhungholdings.com/uploads/ckfinder/files/vamizuvabuxifujusawaxak.pdfIn PDF document text
    • https://sunkamalzemecilik.com/userfiles/file/xaxoginan.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16133ab740981e---gajifizovelowiru.pdfIn PDF document text
    • http://xn--90aoaidn.xn--p1ai/ckfinder/userfiles/files/44731365483.pdfIn PDF document text
    • https://www.anoregmt.org.br/ckeditor/ckfinder/userfiles/files/pibejitolula.pdfIn PDF document text
    • https://merohamro.com/ckfinder/userfiles/files/37527974787.pdfIn PDF document text
    • http://ajej.pretty-match.com/upload/files/vomadujoturoxadonozi.pdfIn PDF document text
    • http://dribblebar.pl/userfiles/file/depug.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/of538b43b6lqtlb826n381819e/mazowimedemowagevegujozid.pdfIn PDF document text
    • http://italianopizzeria-pg.com/uploads/files/82097322629.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_off0000c018.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC018 18360 bytes
SHA-256: 79da86f886f7edb6a3934f7dc7549395b60772021694f465336524aa47e5710a
font_01_sfnt_off0000ef8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF8E 10292 bytes
SHA-256: 748af32d1e137e15eace5fd9cd86dacd0489ac3cec27b4f0314acd0173834579
font_02_sfnt_off000106d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1