Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a1d1da6318c108c…

MALICIOUS

PDF

80.8 KB Created: 2021-09-21 23:56:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 922af5ec29bb72592be8925726920d59 SHA-1: 06a069076ed9e084c2a65d3f205cac2726fbfc0a SHA-256: 8a1d1da6318c108c8a0337e0eb872ef722771d209ee13522a1e5abc65d602200
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of multiple external URI heuristics and link farm indicators further supports this assessment, pointing towards a tactic of directing users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://998.geektic.com/geektic/files/dodolerepiv.pdf In PDF document text
    • https://bestcoloringpages.com/userfiles/file/93751230758.pdfIn PDF document text
    • http://baovethanglongmb.com/upload/files/belajiras.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/11389933527.pdfIn PDF document text
    • http://basketaci.cz/UserFiles/File/16712520555.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a80a1bfcc5---79705884135.pdfIn PDF document text
    • http://hamlineparkplaza.com/assets/amund/ckfinder/userfiles/files/27595089009.pdfIn PDF document text
    • http://www.jobsincrete.gr/images/_user_na/file/xodokisodezonatuterame.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/161478de40c0b2---64231611404.pdfIn PDF document text
    • http://budka39.ru/files/nepupiwodatewuv.pdfIn PDF document text
    • https://vinasimex.com/uploads/file/57804019067.pdfIn PDF document text
    • https://chilepools.com/contents/files/74853153616.pdfIn PDF document text
    • https://www.mppoa.cloudlinesystems.com/assets/ckfinder/userfiles/files/kilabotajo.pdfIn PDF document text
    • http://millionsdiscount.com/mo_images/files/tarakubixegazav.pdfIn PDF document text
    • http://aeklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bumogomunaziwukiwotux.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/xoduzibu.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/161336d28bfb7a---kemafef.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bbc2c211c0---rexopiledujuvijoti.pdfIn PDF document text
    • http://trungtamsangloc.vn/uploads/ck_upload/files/12836330123.pdfIn PDF document text
    • http://cukiernia.eu/upload/files/xisowunofudunejuf.pdfIn PDF document text
    • http://ventensis.lt/public/ckfinder/userfiles/files/63044793077.pdfIn PDF document text
    • http://praguetransfer.com/files/file/ketupuwadogasukuzasi.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1613b5b11c6059---39491096002.pdfIn PDF document text
    • https://theshamrockpublecco.it/file/marixizipoxujejat.pdfIn PDF document text
    • http://edumedcare.pl/upload/files/23343441553.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=android+app+display+namePDF 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_off0000d2c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2C5 19476 bytes
SHA-256: 13d618046f3c342ac4768620c9b418abf84b2c9fe0ff65e5e8a91bdd4d60b6b5
font_01_sfnt_off00010556.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10556 10548 bytes
SHA-256: 3d191cf0bec57adb6d0d421b5d36d93f99fb553210439f40716ec8eded66567a
font_02_sfnt_off00011d55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D55 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1