Malicious PDF — malware analysis report

Static analysis result for SHA-256 87c570cac7fb803c…

MALICIOUS

PDF

82.8 KB Created: 2021-09-09 16:20:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4459b0037a89fa90071bc0a957ad73fe SHA-1: 7fd099f3fbe3a054c195226aa7c349c61c611705 SHA-256: 87c570cac7fb803c5a55c7a2a6e7845043da394f99d9eb602a29ec2857c719cd
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs pointing to a link farm, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The sample's structure and URL patterns are consistent with a malicious document designed to exploit users via a malicious attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://atlastoursntravels.com/userfiles/file/27986989105.pdf In PDF document text
    • http://dieukhactransam.com/uploads/files/busiri.pdfIn PDF document text
    • http://dennehylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/49588633859.pdfIn PDF document text
    • https://viboot.traigiongthuha.com/ckfinder/userfiles/files/zotibine.pdfIn PDF document text
    • https://simpangkanan.com/contents/files/13906209527.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16135172ae3b2f---wegigabogililiraja.pdfIn PDF document text
    • http://obkladlazby.cz/userfiles/file/loxurorevugolokixarixis.pdfIn PDF document text
    • https://www.aaptuk.org/ckfinder/userfiles/files/zomulovuzewaligigagat.pdfIn PDF document text
    • https://softwebstar.com/shop/userfiles/file/81373702641.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138059347986---53882437182.pdfIn PDF document text
    • https://ncltandatbar.com/home/ncltandat/public_html/dowalumniusa/ckfinder/userfiles/files/xewoligiga.pdfIn PDF document text
    • https://malinaionescu.ro/userfiles/file/7778437034.pdfIn PDF document text
    • http://onfireinteriors.com/userfiles/pafilox.pdfIn PDF document text
    • http://sasolution.kr/userfiles/file/rawimenuwuporebasiwaze.pdfIn PDF document text
    • http://pharmabiosolutions.com/filespath/files/20210907161534.pdfIn PDF document text
    • https://www.vignolaweb.it/ckfinder/userfiles/files/71116194893.pdfIn PDF document text
    • http://kfnmdg.com/upfolder/e/files/20210907232039.pdfIn PDF document text
    • http://russia-ex.com/images/blog/file/27052465983.pdfIn PDF document text
    • https://thefertilizerproductionline.com/d/files/83020125652.pdfIn PDF document text
    • https://yourownadviser.com/ckfinder/userfiles/files/56284705975.pdfIn PDF document text
    • https://adikkedua.com/contents/files/donizipabovogutajuxoxa.pdfIn PDF document text
    • http://delve-cr.com/uploads/velimegojuvivavenedomo.pdfIn PDF document text
    • http://mevlanaasm.com/resimler/files/jusimapupe.pdfIn PDF document text
    • http://yevres.fr/ckfinder/userfiles/files/dosufavogiruf.pdfIn PDF document text
    • https://retake.dk/ckfinder/userfiles/files/solisexabiwomide.pdfIn PDF document text
    • http://isagenixmakessense.com/ckfinder/userfiles/files/75111744223.pdfIn PDF document text
    • http://lawfirm.vn/MINH/user_files/file/nazasubit.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=avengers+alliance+2+apkPDF 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_off0000d1d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1D5 22956 bytes
SHA-256: 82b2caa091a76526a3f41124c12bfc308d7ebaf3aa17e4b3ff710f6d80e89811
font_01_sfnt_off00010d2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D2D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012544.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12544 10592 bytes
SHA-256: 5c9a18f8f3d5343bfa326cfbf14bb28ca416ab5ba30d991a7d674cbe1b66e040