Malicious PDF — malware analysis report

Static analysis result for SHA-256 850b8b18816df7b0…

MALICIOUS

PDF

85.3 KB Created: 2021-09-10 21:12:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5085f1fc28e144716287578b6479b1c8 SHA-1: 963212f3576aec84d222c097929ae8895efa63b6 SHA-256: 850b8b18816df7b0d5d8fadf50886afdbfaa4206177aa1b235429683ec8a50e7
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with attempts to trick users into downloading further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://dwitunggaljaya.com/sitefiles/file/5950367343.pdf
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613a459db10cb---15706671628.pdf
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/161303d7746a55---jodavikazadot.pdf
    • http://parateam.cz/file/54994150512.pdf
    • http://srividyaastrology.com/userfiles/file/suwaboxamujikavetonuzumu.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/161327e69d8553---7154498184.pdf
    • http://www.saletime.gr/admin/fckfiles/file/woxide.pdf
    • http://atya.eu/files/file/57813037502.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16134ddaef357e---45435170801.pdf
    • http://ansatrans.ru/admin/ckfinder/userfiles/files/bavadewugevunuvaz.pdf
    • http://abwingsde.com/uploads/files/dabozimajabevasib.pdf
    • https://marcuspietrek.de/MARCUS/files/file/17695243074.pdf
    • https://ladymamashop.com/uploads/files/202109071632139254.pdf
    • http://synagoge-stommeln.de/ckfinder/userfiles/files/50411841135.pdf
    • https://www.leadercaravans.com.au/application/third_party/ckfinder/userfiles/files/godofekinemi.pdf
    • http://duet-czluchow.pl/userfiles/file/57984919626.pdf
    • http://tokyoto.pl/UserFiles/file/5123073841.pdf
    • https://campermagazine.tv/public/file/28440647833.pdf
    • http://alessandrobelleseveterinario.eu/userfiles/files/95348645813.pdf
    • http://ark-mr.com/data/home/qxu2063190031/htdocs/uploadfile/files/19219460422.pdf
    • http://fishingas.com/userfiles/file/26135147889.pdf
    • https://intrastorg.com/userfiles/file/definoje.pdf
    • https://ptkas.com/kingkong/userfiles/files/lekigutibigim.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=free+recharge+mod+apk
    • 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_off0000e7b1.bin
b5759c83666e7d4461450d23d208e25b7af68ebbd0a68fd5eb4dbd0fb045506a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7B1 10524 bytes
font_01_sfnt_off0000ff61.bin
2cf00ba3b0c95a2196821ffb2c5275ceb8df5dc0ecb6099734f0f2596df5a584
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF61 18800 bytes
font_02_sfnt_off0001302d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1302D 16792 bytes