Malicious PDF — malware analysis report

Static analysis result for SHA-256 a90ddef0f87e17c7…

MALICIOUS

PDF

68.8 KB Created: 2021-05-06 18:47:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-30
MD5: 01990aab00b5a7af71e01a2a800e5eff SHA-1: 284b869bf5117652cbbdfb43e4d1f9d34d742977 SHA-256: a90ddef0f87e17c7ec623c50393802e1df2890bf729bbb59381f1a67d2290d6b
196 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations, suggesting a link farm or phishing lure. The ClamAV detection and ML classifier strongly indicate malicious intent. The embedded URLs and the nature of the heuristics point towards a phishing or malware distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/f2d6b69a1ab5430570b3cf753d7fc02a/dipoxuxuzupolapulila.pdf In PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/ccboarnjoec0uaombnq0qt403d/wekisemesitanina.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/09f1a4f7f86321ab9378621fe8ef7ce9/biwewiliraket.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/8373c9d7b7d85d0238b58754bfcf94d0/1694451195.pdfIn PDF document text
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/n3gjimgvvqpmf1qhovtbgiijuo/81196892409.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606f67545ccb5---dajagofi.pdfIn PDF document text
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077527acf6ee---jodavedokirija.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/gugevegejotetanodowutakav.pdfIn PDF document text
    • http://ankurgroups.com/userfiles/file/pinasitav.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ab56511aff---50707559198.pdfIn PDF document text
    • http://forter.vn/hinhanh/file/tubaviretilowaxejixavaki.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160818f994eeb5---jolul.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/19dc8598d938f1143057a35c0185e1a3/87571579005.pdfIn PDF document text
    • https://davebakeragency.com/wp-content/plugins/super-forms/uploads/php/files/1b7129e4ccdfff7c804b68102b7f2ea2/30968404023.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=performance+test+macbook+air+2018PDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cecb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCECB 5720 bytes
SHA-256: 275f9c1ea8aa36447b8813fc7d7b1aa76cca78432626bda71c10b83d2c201db5
font_01_sfnt_off0000e22e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE22E 10572 bytes
SHA-256: 6a39d18a6087c5fa5080793ca56f882b3a00a7b38d2259e9ab017eda7b121eac