Malicious PDF — malware analysis report

Static analysis result for SHA-256 d991b00727a13a10…

MALICIOUS

PDF

83.4 KB Created: 2021-09-22 10:02:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 6e68fc6b8f0cb431cab6037498ba77a6 SHA-1: f7315e88215ab3bce4b3d901caee17414784cd4a SHA-256: d991b00727a13a1061c1d77b26a1326e2f509c5cdf165c689b119096448541fd
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm or SEO poisoning attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The embedded URLs and the nature of the heuristics point towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/f14c6b2fe9c1fb1576ce1de11b998767/divekewaxak.pdf In PDF document text
    • http://visit-pune.com/userfiles/file/2211937410.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210902141808296.pdfIn PDF document text
    • http://srihemkuntsahibfgp.org/hemkunt/userfiles/file/ripexavo.pdfIn PDF document text
    • https://cortemadera.com/wysiwygfiles/file/97261174311.pdfIn PDF document text
    • https://vieclamlaocai.vn/webroot/img/files/9925428640.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/o7pe644o3rn51o0jk1q6qfnns0/refefovarese.pdfIn PDF document text
    • http://hong-tour.com/FileData/ckfinder/files/20210903_E47FCD37E18AFE9C.pdfIn PDF document text
    • https://www.igescanada.com/ckfinder/userfiles/files/vetimumita.pdfIn PDF document text
    • https://ykitraders.com/UserFiles/file/89073278746.pdfIn PDF document text
    • http://alteredcompta.com/buddha/ckfinder/userfiles/files/sizaripavasog.pdfIn PDF document text
    • http://haitrungkim.vn/uploads/userfiles/file/xulatatege.pdfIn PDF document text
    • http://trineckevzdelavani.cz/webpagebuilder/ckfinder/userfiles/files/lelavadiwesetudesa.pdfIn PDF document text
    • http://xn--49s538bo8ux8c.net/userfiles/file/3503775568.pdfIn PDF document text
    • https://hotnews.md/upload/userfiles/files/23614651965.pdfIn PDF document text
    • http://de.ruben.pl/ckfinder/userfiles/files/xodujivajobew.pdfIn PDF document text
    • https://faresaldabbous.com/uploads/files/27503465014.pdfIn PDF document text
    • http://peoplefineart.com/assets/202109/files/20210904025219175112.pdfIn PDF document text
    • http://marklaliberte.com/fckupload/file/23738432772.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/betibotosamivofo.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/pufufetepolal.pdfIn PDF document text
    • http://ballmillfactory.com/d/files/57114284250.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ad0a53cce4---tewexobozop.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=command+and+conquer+generals+download+for+androidPDF 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_off0000e0ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0FF 17656 bytes
SHA-256: 3d97d4f72721d666836c6dfc33e379450baa746f628067a46129eb02e6b7f1aa
font_01_sfnt_off00010e1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E1A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012631.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12631 11084 bytes
SHA-256: ed5949029fdd311b691cb3e4980e77377ed3feee795e48933713898c0abb3b19