Malicious PDF — malware analysis report

Static analysis result for SHA-256 913dcd18d15d3103…

MALICIOUS

PDF

74.0 KB Created: 2021-03-30 11:22:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: a67b54d65e912a7cafff34dfc72eb7a0 SHA-1: 5c64eb2fb0663e577604188b90fd69b144109581 SHA-256: 913dcd18d15d3103c7fea1e6abe2b75df48680c204e4253d6ff6509d1caaa442
186 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, identified as a link farm. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or SEO spam. While no scripts were directly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://xezojetit.ru/award?keyword=use+of+articles+a+an+the+exercises+pdf PDF link annotation
    • https://cdn.sqhk.co/gavezexu/jciehiK/android_error_google_play_services_keeps_stopping.pdfIn PDF document text
    • https://cdn.sqhk.co/gidenateg/gEc1pgg/zesuvuzowu.pdfIn PDF document text
    • https://lanizozegew.weebly.com/uploads/1/3/5/3/135309184/doxodabezegumegepese.pdfIn PDF document text
    • https://duzigavejad.weebly.com/uploads/1/3/4/5/134513143/dakupez.pdfIn PDF document text
    • https://cdn.sqhk.co/pemiduwegam/0gPgdjB/curve_sketching_of_rational_functions.pdfIn PDF document text
    • https://cdn.sqhk.co/rufosopufu/aIzjdhb/fubume.pdfIn PDF document text
    • https://dotowukigirer.weebly.com/uploads/1/3/1/1/131163902/piwiwuxenaxov.pdfIn PDF document text
    • https://junuwuka.weebly.com/uploads/1/3/4/4/134479395/8332375.pdfIn PDF document text
    • https://cdn.sqhk.co/xugosovemi/CgfrSjc/best_free_music_download_apps_ios.pdfIn PDF document text
    • https://xujopikaxatanow.weebly.com/uploads/1/3/4/8/134850499/lodadadem_wokokorozop.pdfIn PDF document text
    • https://dutitujazekap.weebly.com/uploads/1/3/0/8/130814390/932f9ac6.pdfIn PDF document text
    • https://bojotipawotos.weebly.com/uploads/1/3/2/6/132681617/1992758.pdfIn PDF document text
    • https://tekitoloveda.weebly.com/uploads/1/3/1/0/131070611/8432648.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://661c91a2-68a2-4ae3-aaac-ef96b6cc7894.filesusr.com/ugd/b926a8_1fde6a3c2744402485d94033ebef9fcc.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/divexikav/in_the_heights_lyrics.pdfIn PDF document text
    • https://b40f07b9-a98f-42b6-a6e2-5dc2c82ebb0e.filesusr.com/ugd/e949ea_2d7ea8ffd4f44a169092a72736c90b32.pdf?index=trueIn PDF document text
    • https://af0fe010-594a-4ec7-a26b-e2d78e33490d.filesusr.com/ugd/7d2910_6abd5d4afd3140b398b252af5b664c6b.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/lodazojamuva/71774320809.pdfIn PDF document text
    • https://d3826037-6016-486c-99e9-dc41bc666644.filesusr.com/ugd/b81754_afb7aeb53211453fbb5af27aa7d44bae.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/zedudo/birth_certificate_change_form_illinois.pdfIn PDF document text
    • https://s3.amazonaws.com/gosete/38160994193.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e49d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE49D 5304 bytes
SHA-256: af429ed6db32754e17c3bef49ae3bb441d60f3a169bc37a42e12ace9fe1ce51c
font_01_sfnt_off0000f6aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6AA 10364 bytes
SHA-256: 5af539c22298866ca1751531df69c281e72d11ede5d346f43c3be36e1a38b27c