Malicious PDF — malware analysis report

Static analysis result for SHA-256 856187ee87f3da41…

MALICIOUS

PDF

82.3 KB Created: 2021-05-07 05:53:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 7179bb6092f725b097e1b33abaafd630 SHA-1: 84267a0b874b964fc78014898ef95c8b9c979072 SHA-256: 856187ee87f3da41be5ee5bada6b5295f80e86e04cad26e7f946f561ca7946d0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV detecting it as a phishing trojan. It contains numerous external links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the overall structure indicate an attempt to exploit users by directing them to potentially harmful external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://allytemp.ru/uplcv?utm_term=emoji+apk+for+android PDF link annotation
    • https://www.albispanaderia.com/wp-content/plugins/super-forms/uploads/php/files/14c2933fa7370530f2a343757d3574fd/sojuwexarojaduvowog.pdfIn PDF document text
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/1608924a6af840---wedebaxegiwabe.pdfIn PDF document text
    • http://banhangcongnghe.com/upload/FCK/file/pavexulazudarimatukeme.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081b9574e0a2---nizovuxilej.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/bb51bacb7426e20db036316c1fdb0e37/pidobijororepegetesuz.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/160893cc4c24c8---nenojizuzajozo.pdfIn PDF document text
    • https://mmszke.hu/files/file/sisifi.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609317e8dca9f---xixanopajame.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/a2ea3e731002d08b84e64fb2353a3eb0/38939078519.pdfIn PDF document text
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/vi7k2lgvna7edsonasj5hu366v/funinaviragosekadaj.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ebe2b82cb6---28980061245.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc6999f7dc---51626419320.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/8f1be2750576fddce26c3a238c401a2e/mevurimomegupaxapuj.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/1608d7ac3e3968---dokikazidegeponozaxuju.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0000ec08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC08 5076 bytes
SHA-256: 5b2d4e0451109c09e44680e35f97843408fa5302cba99451507821b938473c95
font_01_sfnt_off0000fd43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD43 11920 bytes
SHA-256: 2ddb2cf096f432ee86cbeea16e14fc87e19ddd5da3b43ecc050f539bd0f40d5b
font_02_sfnt_off00012639.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12639 16088 bytes
SHA-256: 9b6ad5722d12b30ebaf898f562fd4d85af749794f3aca0f1f676e444c262175b