Malicious PDF — malware analysis report

Static analysis result for SHA-256 9cdcc0d7846bf4d6…

MALICIOUS

PDF

87.0 KB Created: 2021-10-08 22:34:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: daeb9b377ac7f9a191491fecd3dd745f SHA-1: a01209c453b708a169e51868f062ea988bd7408a SHA-256: 9cdcc0d7846bf4d6726f9d840c3542ced10cccefae04cbcdb8cc60962841a9e3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the URLs and the PDF structure suggest it may leverage embedded JavaScript for redirection or obfuscation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://oniceh.ru/uplcv?utm_term=fast+and+furious+8+online+movie
    • http://tochuchoinghi.org/files/wojinafikemimide.pdf
    • http://kssi.ir/public/userfiles/file/88648864132.pdf
    • http://lmnn.ru/userfiles/file/denubujelef.pdf
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/38b8e3a1916dc63140f4bb1f69c58cfb/29729196977.pdf
    • http://aotwresort.org/ckfinder/userfiles/files/59898398555.pdf
    • https://vitanov.rs/files/lunisarufobaki.pdf
    • http://k1a.ru/images/files/file/pazidirulerut.pdf
    • https://banifatemeh.org/data/file/pozofiwinagubazoka.pdf
    • http://zhongjiukeji.com/upload_fck/file/2021-9-21/20210921065352358029.pdf
    • http://salukool.ee/upload/userfiles/file/32232143512.pdf
    • https://hoya.mobioptika.hr/UserFiles/file/lodowuvoradiduwetubezanin.pdf
    • http://plenaseguroseprevidencia.com/fotosempresa/files/suxudulejenutegurezera.pdf
    • http://ieltsadd.ir/cache/fck_files/file/xowaguk.pdf
    • https://31app.com/userfiles/file/54281114518.pdf
    • http://deshdunya.com/blogimage/file/78468439343.pdf
    • https://postelezmasivu-praha.cz/ckfinder/userfiles/files/11119037853.pdf
    • https://stoneappeal.in/FCKeditor/file/jefobapof.pdf
    • https://homeuu.biz/upload/ckeditor/pages/files/segemotizinabugod.pdf
    • http://rc-modeller.se/images/file///jobabosomuromesasuvajelos.pdf
    • https://www.bramfordgc.co.uk/ckfinder/userfiles/files/7405608109.pdf
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143e057dae0d---madilavujapovoze.pdf
    • http://tdvvietnam.vn/webroot/img/files/fiwegapibapamuvagaf.pdf
    • https://floraplant.gr/FCKeditor/userimages/file/gunufelopasojodar.pdf
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/vnh2m5mqqhppl56qgb4dvsjrcu/lotadula.pdf
    • http://hindustanadvancedsolution.com/t/tutorfirm/uploads/ck/files/82864732081.pdf
    • https://er-cardiff.com/eurostyl/photos/file/92079125328.pdf
    • 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_off0000ebc8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBC8 16792 bytes
font_01_sfnt_off000103da.bin
0dc5097795c8baeb3142c4875f9268ade96549cfcbf66c6eb1cb14f1d4dfbc01
pdf-font-stream PDF embedded font (sfnt) at offset 0x103DA 19140 bytes
font_02_sfnt_off00013535.bin
42a3527425f51e0fad194e554e82ef6c0ecdb56ada9f977450400c15ede86196
pdf-font-stream PDF embedded font (sfnt) at offset 0x13535 10868 bytes