Malicious PDF — malware analysis report

Static analysis result for SHA-256 afd5d26433735353…

MALICIOUS

PDF

80.1 KB Created: 2021-05-20 22:48:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 93d84216459fd4a3c21fa7195daad96f SHA-1: 38176ce3598bfc9221653e3b4ef9acd42b7c140c SHA-256: afd5d26433735353cc3f80172e889ef1445306713f21526e7b406a4722f4a835
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous external links, many hosted on compromised WordPress sites, suggesting a link farm or SEO manipulation tactic. The ML classifier strongly flagged this PDF as malicious. The presence of embedded URLs and the nature of the heuristics indicate the document is designed to redirect users to potentially harmful content or exploit kits.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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://krisoc.ru/uplcv?utm_term=gloud+games+mod+apk+english+version+download PDF link annotation
    • http://mirandatutoringcentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607851240dcc6---zamupenexajigodojosomo.pdfIn PDF document text
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/b50a42a45172ac05e7462dd88309d372/somomewelavizujuvafik.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/160982efedee5f---tusivuwavibobukelijur.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//reribamuw.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608303e2ab5c0---dilikajeneki.pdfIn PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/c7005c4d7c3d66bcd6f5f70bb258d7e2/57672216112.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160944a8a8e012---53346238205.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607d55247defd---pomep.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fa939dbea2---70165952661.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/tosekt7rj3rr24edog6ohbevv6/11389440136.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/31071047542b0b8ae0ad5c80b3d3167a/80574746825.pdfIn PDF document text
    • https://rlvanstory.com/wp-content/plugins/super-forms/uploads/php/files/21388234633c5e962bda1354ba5931b7/povogimaxifelulopivimem.pdfIn PDF document text
    • https://www.aceitedeoliva.com/wp-content/plugins/super-forms/uploads/php/files/36bc51c45484fb50aaffbb097cadf9f2/tenigulilinegasowos.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/0f1435465f43dca33a15be1044032e88/garirovanato.pdfIn PDF document text
    • https://sygimportaciones.com/wp-content/plugins/super-forms/uploads/php/files/d6t07rri19fvrtulr8b1l4r0b2/pifivuvulevifudo.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dc2561ccc1---66673561859.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_off0000dc2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC2B 5620 bytes
SHA-256: 8727d18de336529dc03349fad5a2150a9eb898984c32994e6a7e6542b10a14fd
font_01_sfnt_off0000ef36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF36 10428 bytes
SHA-256: 9151d4ca61f8262fe8f800f5f58d003ae708060ff34cb8a5257847fad06c97a1
font_02_sfnt_off0001129c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1129C 18604 bytes
SHA-256: 8ab163a972fde83686bf59ebe15ab7415e58aab78f4d8053ce02ad6be109fc51