Malicious PDF — malware analysis report

Static analysis result for SHA-256 dec236ba03886206…

MALICIOUS

PDF

79.8 KB Created: 2021-09-06 01:12:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b175fcacfb1743902a2d263d4b687af2 SHA-1: 5a1a4e91985a927e258683a080fdfbaf1dd0aa27 SHA-256: dec236ba03886206f4c8ac605b699e7e9bae9feb05ee19e8a7da52c97eb7ebf2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to compromised websites and link farms, a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links suggest it's designed to lure users to malicious sites, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://laborke.ru/uplcv?utm_term=six+hours+one+friday+free+pdf PDF link annotation
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/0620a9cb5d36221c97362985604d9434/79880189659.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3a74cc557---poniselusunelubumizujeva.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160b66e21b686e---lelegujoto.pdfIn PDF document text
    • http://archerelectricsupply.com/userfiles/file/zifidusuzidofadepigut.pdfIn PDF document text
    • https://saam.vn/images/content/file/12334643797.pdfIn PDF document text
    • https://law.com.sg/wp-content/plugins/super-forms/uploads/php/files/b773d2e20b09ec16c15840899e4f4514/demawefuvovofu.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ed003f0341e---pipebe.pdfIn PDF document text
    • https://vidaleve.net/ckfinder/userfiles/files/bapalut.pdfIn PDF document text
    • http://voxel-avocats.fr/uploads/file/34489280317.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd118f3abfa---wekezewolewekaxuvuv.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ce782045513---pizudubizerorek.pdfIn PDF document text
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/04e521745018b50a16abfb9ff20f8d72/gapibujoda.pdfIn PDF document text
    • http://clubsahdianagalati.ro/upload/editor/file/8164129186.pdfIn PDF document text
    • https://chp-travel.ir/data/file/dojigoladazonenubifurugu.pdfIn PDF document text
    • http://ukicda.com/admin/fckeditor_upfiles/file/2021062102480980554.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/g6efkdl8iqfduhsej2k9ot8pbi/bidalimazatesiwikoforog.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609055eddddec---pidetibekanowofirukuxu.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/d0e08b24c192db0193ef8d183ff6d983/pigojuligotoso.pdfIn PDF document text
    • http://er-trans.com/img/produkty/files/tufuw.pdfIn PDF document text
    • https://fontaine-eva.fr/userfiles/files/revunom.pdfIn PDF document text
    • http://prestopc.it/upload/file/darurax.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/16088ded3ba9e5---89623656945.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb7baa0334---tujisilager.pdfIn PDF document text
    • http://brooklinehs1964.com/clients/6/6a/6a3559cec3eb17f551da2d864c8c85ab/File/wiladurafuvelivupukotod.pdfIn PDF document text
    • 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_off0000d0a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e8c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8C0 10840 bytes
SHA-256: 68a344d300768bd60b98c7d40a804b17be35f85dfb6f3f0394d9c103b0827765
font_02_sfnt_off000101b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101B3 17860 bytes
SHA-256: 53204f2eb805c5f0c543e949c24c2a311a41801f30247a2e6c547ccc5fca690d