Malicious PDF — malware analysis report

Static analysis result for SHA-256 b15ac8ddceba8ce0…

MALICIOUS

PDF

74.1 KB Created: 2021-09-14 13:31:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a62c5ed388646fccfee7d7b2ed3721b7 SHA-1: 5481625b8d7236a54fa7b6cba505b5c9931393fa SHA-256: b15ac8ddceba8ce062794bc8ef69d6485289e1d606736c6c77ab36d5886fab7d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is often used to download and execute further malicious payloads. The presence of multiple links pointing to compromised CMS upload storage and disposable hosting, combined with a high ML classifier score and ClamAV detection, strongly indicates malicious intent. The document body is unreadable, but the heuristics and embedded artifacts suggest a phishing or scam attempt designed to trick users into downloading malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16140764401b15---sekafejamowaf.pdf In PDF document text
    • http://grandinhr.eu/images/user/file/9605738848.pdfIn PDF document text
    • http://nebovsem.ru/app/webroot/files/files/52716024318.pdfIn PDF document text
    • https://edarky.net/data/file/79008970480.pdfIn PDF document text
    • http://jtylek.pl/Upload/file/28142296555.pdfIn PDF document text
    • http://china-miyaco.com/img/file/202195144641.pdfIn PDF document text
    • http://erex.hu/upload/file/5775884903.pdfIn PDF document text
    • http://eachfun.com/ckfinder/userfiles/site_eachfun_com/files/43646317965.pdfIn PDF document text
    • http://studiopassarotti.it/userfiles/files/33817962489.pdfIn PDF document text
    • http://gramercy-grand.ru/files/file/14042202898.pdfIn PDF document text
    • http://huerural.com/uploads/image/files/61429352551.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134a74a4ebad---nilav.pdfIn PDF document text
    • https://maxtarget.by/ckfinder/userfiles/files/90783485744.pdfIn PDF document text
    • https://dienhoanghean.com/upload/ck/files/10467142708.pdfIn PDF document text
    • http://fresh-j.info/images/uploadedimages/file/kuwapabafeko.pdfIn PDF document text
    • http://www.enfersalus.com/ckfinder/userfiles/files/biwasumujowizironuka.pdfIn PDF document text
    • http://mayepnuocmia.vn/data/ckfinder/files/nosemoselorigezozok.pdfIn PDF document text
    • http://axwelindia.com/uploads/kunuzojewopokevu.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613a7b7a3134b---4828000109.pdfIn PDF document text
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/fudas.pdfIn PDF document text
    • http://nawaress.com/webroot/js/ckfinder/userfiles/files/kokugafewerosaj.pdfIn PDF document text
    • http://alacarte-design.de/userfiles/file/33512923581.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=advanced+selling+strategies+by+brian+tracy+pdfPDF 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_off0000b9f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9F6 18244 bytes
SHA-256: f86fe9ed4cecd9a3ef67c9a31f1cabf26a76a63508527bc09fce31ce9157181e
font_01_sfnt_off0000e951.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE951 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010168.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10168 10976 bytes
SHA-256: d54b85da66523de8d7c7315c03002313dbc0ac337f811b615cbb3a81efd18781