Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b4da9f33373ec5e…

MALICIOUS

PDF

75.6 KB Created: 2021-07-27 04:03:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7bb2bb1d6421a2eb5dd6866a893e3265 SHA-1: f0898f32b4f103e3044e71e194dfb52f163aa0ec SHA-256: 8b4da9f33373ec5e260e3b88754e791d512f8b1a039baca46a7bb71f6c8c1847
164 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of a link farm on disposable hosting and compromised CMS upload storage suggests an attempt to distribute malicious content. The heuristic for a visual download button further supports a social engineering lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://starwindows.ie/ckfinder/userfiles/files/12665501670.pdf In PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f4183a80937---97959570714.pdfIn PDF document text
    • https://majubesar.com/contents//files/bajawoser.pdfIn PDF document text
    • http://alpha-cp.com/userfiles/file/30073345059.pdfIn PDF document text
    • https://vleek.com/uploads/files/gagaruto.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c11147269ab---76348429482.pdfIn PDF document text
    • http://aisef.org/uploads/userfiles/file/file/46300072151.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9e1005f2cc---1873847555.pdfIn PDF document text
    • http://mobilesamara.com/img/files/file/zazevowiduxoga.pdfIn PDF document text
    • http://bulk-supplies.com/userfiles/file/44863565880.pdfIn PDF document text
    • https://binarbaidservices.com/public_html/userfiles/file/58932549095.pdfIn PDF document text
    • https://dynasty888.com/image/files/20210701_175135.pdfIn PDF document text
    • http://sitoad.com/bbqjoekey/files/202107250150187617.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1608c5c32d8f52---popopiz.pdfIn PDF document text
    • https://datajournonepal.org/files/viligawukepofuzotofov.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/dff82e71b6c728125067d2e9b10c34db/67345905006.pdfIn PDF document text
    • http://come2menorca.com/images/file/manelagofupivixatub.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/fqcd4sv1ggrjkpmmjdi06nslu6/70524799588.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16095d58f61792---nasijunanimujenugidifa.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/160a01e91e2bab---89096415790.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160edd27366d98---sakidonakifuvupak.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/ubgivrmm73gfc5ani1bdpscaa5/bogamufok.pdfIn PDF document text
    • http://hoteldarim.ir/basefile/hoteldarimir/files/54315505.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=advanced+dungeons+dragons+player%27s+handbook+pdf+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_off0000c184.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC184 11320 bytes
SHA-256: 424fac707e610c61ae6b07ceef5a33dc595ddcc953d39c005a8dc68ddff29a0d
font_01_sfnt_off0000dbcc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBCC 16524 bytes
SHA-256: 955d636713e2872dbff46e7a20506e42d28cc409a84e3c131d18134bc2d65861
font_02_sfnt_off000105fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1