Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8b6d4ade6398e41…

MALICIOUS

PDF

87.2 KB Created: 2021-09-10 22:19:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 037271160c464bf4cdb5fcaea73c68b3 SHA-1: db973766eba5b4406fe9f9f6675bb2984a74fb29 SHA-256: a8b6d4ade6398e417cc0ac1f91151555ae5a44051e5f2131a2344443c88676c9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised CMS upload storage or disposable hosting, indicative of a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://smidgel.ru/uplcv?utm_term=how+to+backup+data+from+lost+android+phone PDF link annotation
    • http://morecoredesign.com/images/imageUps/files/vozadi.pdfIn PDF document text
    • https://maisonforville.be/documents/file/70847835664.pdfIn PDF document text
    • https://aicpwdosaeast.com/ckfinder/userfiles/files/zubosokakudoxofovim.pdfIn PDF document text
    • http://iswii.net/ckfinder/userfiles/files/40848795877.pdfIn PDF document text
    • https://abzesolar.com/uploads/files/51103901583.pdfIn PDF document text
    • https://www.clinicaepilepsia.cl/ckfinder/userfiles/files/8252258564.pdfIn PDF document text
    • http://ntvietnga.com/upload/files/jirofumo.pdfIn PDF document text
    • http://eventechsite.com/files/files/44531320104.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/fl8ep6herfd62bl8egqc13rpvc/pipililidefomevixol.pdfIn PDF document text
    • https://ximatinhdongnai.com/app/webroot/files/images/pages/files/pezuz.pdfIn PDF document text
    • https://jairdefreitas.com/ckfinder/userfiles/files/bivojelizofupe.pdfIn PDF document text
    • https://newcar-rental.com/uploads/files/202109030959308580.pdfIn PDF document text
    • http://telekommarketing.com/firme_data/files/ramamejovavebefo.pdfIn PDF document text
    • http://xn----0tbbbfo0f.xn--p1ai/userfiles/file/warurixipaled.pdfIn PDF document text
    • http://tongchangkj.com/uploadfile/file///2021091101424891.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161391c2e5a95e---kegunojogekotukexe.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/16135edc7261bd---xotazomuzonowalepuxakas.pdfIn PDF document text
    • http://15881588.com/ckupload/files/tajotarifogepasagazigukas.pdfIn PDF document text
    • http://ippon.lv/uploads/File/94433399467.pdfIn PDF document text
    • http://currycornersugarland.com/admin/images/file/86824186987.pdfIn PDF document text
    • http://metalltechnik-kutschi.at/fosarobeme.pdfIn PDF document text
    • http://boxerdapolenta.com/cmsimple/images/file/kikekub.pdfIn PDF document text
    • http://cu-mbc.com/ckfinder/userfiles/files/zujigonepetufenela.pdfIn PDF document text
    • http://hainescentreasia.com/images/file/89749791289.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/1612f056468cc3---bedowezukoma.pdfIn PDF document text
    • http://podolsk-kondicionery.ru/upload_picture/file/bikogijosoz.pdfIn PDF document text
    • http://lmleadmanagement.com/userfiles/files/fodolug.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_off0000ee11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE11 17620 bytes
SHA-256: 88ba5674602afd5fe5dcbd528f74a5ddf8ea204b5cedce540fae3b92cd9c715b
font_01_sfnt_off00011c29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C29 11296 bytes
SHA-256: ea615f077172dadfaeaee1e37c7b9c1d465012d679dc1d74efcb0c28d45a96bb
font_02_sfnt_off00013658.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13658 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1