Malicious PDF — malware analysis report

Static analysis result for SHA-256 86ae4bc4a19cfc6b…

MALICIOUS

PDF

85.4 KB Created: 2021-09-14 12:05:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a9f1e1510ac0daa879a1a40eef45bf26 SHA-1: 5b343101bf71c79ad0eb4421484ce631acbcd185 SHA-256: 86ae4bc4a19cfc6bb546892d5ae1562b2ff151c578201e7bf4d9cfb98d432d8b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm designed to redirect users to various PDF files hosted on multiple domains, some of which are identified as compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were directly extracted, the structure and URL patterns are consistent with a phishing lure attempting to trick users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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 http://pcwenhua.com/uploadimg/file/1630518359563072656.pdf In PDF document text
    • https://nepalfinepashmina.com/userfiles/file/33783958816.pdfIn PDF document text
    • http://naso10.com/userData/board/file/godogopov.pdfIn PDF document text
    • http://hattingtoemrerogsnedker.dk/userfiles/file/44960216711.pdfIn PDF document text
    • http://abcbyspu.com/ckfinder/images_store/files/93627035047.pdfIn PDF document text
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/84b1cd88eb761aea0497de722a36a199/kesejotapadidaza.pdfIn PDF document text
    • http://wxeina.com/userfiles/files/89158646297.pdfIn PDF document text
    • http://ned.ru/uploads/files/dijidirepolikibalo.pdfIn PDF document text
    • https://millinerandassoc.com/files/file/zamununubejefakipodejid.pdfIn PDF document text
    • http://abarappresentanze.it/userfiles/files/jogomugavivava.pdfIn PDF document text
    • http://qigong.ru/userfiles/file/55555926366.pdfIn PDF document text
    • http://kerekagy.hu/UserFiles/file/70472958622.pdfIn PDF document text
    • https://angkortaxiservice.com/userfiles/file/galakukakidebanusel.pdfIn PDF document text
    • http://gz-theoutfit.com/UploadFiles/FCKeditor/20210909090549.pdfIn PDF document text
    • http://floral-design-lindgens.de/userfiles/file/mimavuluw.pdfIn PDF document text
    • https://lockerova.eu/admin/upload/documents/66204935299.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161303facbb729---38246445612.pdfIn PDF document text
    • https://anhhuynoithat.com/asset/files/82635840858.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/16133a5d77eb06---27521839197.pdfIn PDF document text
    • https://imagebrandstudio.com/userfiles/file/zezuwamubupikugela.pdfIn PDF document text
    • http://grafitym.kz/files/file/74953201751.pdfIn PDF document text
    • http://ministryofrum.com/memlogos/file/jifer.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613446339ba26---pafotesavajamalireleto.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=the+hobbit+book+downloadPDF 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_off0000eaa1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAA1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000102b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102B3 18124 bytes
SHA-256: 8536e538e699c0c3830683072604d937152bb79236a9f7a1514418fbecfe1b04
font_02_sfnt_off00013152.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13152 10356 bytes
SHA-256: ef6261229366c8017130063f315ab78d9dd4626399cea71eda1c2ffb67953f8d