Malicious PDF — malware analysis report

Static analysis result for SHA-256 d157722b8aed2133…

MALICIOUS

PDF

82.4 KB Created: 2021-09-14 12:15:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: de4edb643045883011d556a4429fd658 SHA-1: 9d7a16ce762ec3bca5445a22f457993381145e46 SHA-256: d157722b8aed2133f58dc08eed1901cae53553eaab3d0f2f24ae967edacdd041
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://schokoladenfontaene.de/idata/xewijirixefa.pdf In PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614065d6c4414---48612264189.pdfIn PDF document text
    • http://foodchemsino.com/d/files/27133729197.pdfIn PDF document text
    • http://jeanthompson.nl/ckfinder/userfiles/files/9933611585.pdfIn PDF document text
    • http://www.gieskestukadoors.nl/ckfinder/files/files/barezemaroxoda.pdfIn PDF document text
    • https://www.truckersplantparts.co.uk/ckfinder/userfiles/files/tapekex.pdfIn PDF document text
    • http://tykhchem.com/upload/files/39406762311.pdfIn PDF document text
    • http://videlec.be/ressource/file/wadufawos.pdfIn PDF document text
    • http://fsgzb.com/upfolder/e/files/20210911171555.pdfIn PDF document text
    • http://debsecond.net/UserFiles/File/rosuka.pdfIn PDF document text
    • http://kbidc.kr/upload/editor/file/1630798619.pdfIn PDF document text
    • http://wonsakai.com/uploads/files/81330354777.pdfIn PDF document text
    • http://infinivideo.hu/sites/infinivideo/files/59651494621.pdfIn PDF document text
    • http://floramarble.com/uploads/sisezap.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613f4e3e9c097---goguwitikubozuje.pdfIn PDF document text
    • http://gpba.ge/admin/ckeditor/ckfinder/userfiles/files/14561915643.pdfIn PDF document text
    • https://voolabs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f84c783ac5---ridadozinovuvusamo.pdfIn PDF document text
    • https://classykitchen.pl/web/uploads/files/mukububabelusok.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/08fef351fa9ea0cee31ff6e6caff2653/6870204237.pdfIn PDF document text
    • http://fnathservices.com/upload/file/rizugodowo.pdfIn PDF document text
    • https://vongtaytramhuong.vn/upload/files/korovowuzubigavumitasigef.pdfIn PDF document text
    • http://srs-budapest.hu/uploads/files/zatabimavuxetufobepaw.pdfIn PDF document text
    • http://gtlitalia.com/userfiles/files/6641309473.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=stream+android+screen+to+tvPDF 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_off0000dde6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDE6 17576 bytes
SHA-256: f90c2839f44c4b7888940faef9b1d0c466615683bf9452d73aedbbf4e1728a8b
font_01_sfnt_off00010b46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B46 10624 bytes
SHA-256: aea8f651d64ad667ffd1be30e8b059b8a3e0815836c46d953e383e59d0b5f230
font_02_sfnt_off00012397.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12397 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1