Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb9d5489f5813c2b…

MALICIOUS

PDF

89.0 KB Created: 2021-09-09 23:25:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 736457fc9191ad4de1d023363d2781c6 SHA-1: d9d67affb49eecb9a26c2937b9b905941e989052 SHA-256: cb9d5489f5813c2b36f32f2953883dc13e274613a862267b89de025895fa7561
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on potentially disposable domains. The presence of numerous unknown URLs suggests an attempt to distribute malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://golfproradost.cz/webpagebuilder/ckfinder/userfiles/files/49620093671.pdf In PDF document text
    • http://swhos.com/upload/files/81288978195.pdfIn PDF document text
    • http://ck-tct.ru/userfiles/file/jifukexaberavivu.pdfIn PDF document text
    • http://coumert.com/images/file/vezevofabenego.pdfIn PDF document text
    • http://panyuchen.com/ckfinder/userfiles/site_eachfun_com/files/30480977607.pdfIn PDF document text
    • https://ropaalmayoreo.com/images/userfiles/file/gubuzosesalora.pdfIn PDF document text
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/38050815489.pdfIn PDF document text
    • https://egyptsuntours.com/userfiles/files/tonopavaforuger.pdfIn PDF document text
    • http://hrampetraipavlavosstanovlenie.ru/content/images/user/file/misufofobidunifon.pdfIn PDF document text
    • http://studiolorenzino.eu/userfiles/files/lakewidipodobifobuwik.pdfIn PDF document text
    • https://mcq-exambd.com/app/webroot/ckfinder/userfiles/files/59118879993.pdfIn PDF document text
    • http://homokkepek.hu/editor_up/mabopoveniluguxiv.pdfIn PDF document text
    • http://ufnk.fr/app/webroot/files/file/45685563648.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/87ccba63083772f0bab79af02e0ea150/kadozebavubenanejovanirur.pdfIn PDF document text
    • https://ww150004.linebot.net/upfile/files/20210905123614.pdfIn PDF document text
    • http://dietgame.net/admin/fckeditor/data/file/20210910001818.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16135a855cdf11---24217009992.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613821a97808d---kesokan.pdfIn PDF document text
    • https://cartolmania.it/file/81017560693.pdfIn PDF document text
    • http://wxbeimei.cn/upload/ckimg/files/202109091505489070.pdfIn PDF document text
    • http://tetrafluoro.com/upload/files/71611548618.pdfIn PDF document text
    • http://aweibel.com/Photo/file/64935523190.pdfIn PDF document text
    • https://quangcaowebsitecomvn.xemlaco.com/uploads/files/44676407896.pdfIn PDF document text
    • https://dispecom.com/cms_dispecom/sgi_userfiles/userfiles/files/83825931118.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=watch+movies+hdPDF 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_off0000f8b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8B6 18080 bytes
SHA-256: 7b5cfb822f798b9e9f10fb53b1e065b620f1f0112da4eab48eb7baeac1049b6b
font_01_sfnt_off000126c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126C0 10444 bytes
SHA-256: 7db5c77702d754ab42b5fce554853f478d202c1f70af41d96fdddbc26ec0c6b5
font_02_sfnt_off00013e8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E8F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1