Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ccb3720cf1ea10f…

MALICIOUS

PDF

77.5 KB Created: 2021-03-22 03:28:07 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: 33ecaa8603cb818f1aa159b14a0771f1 SHA-1: c628448a3b156d92c025b42119e1a3078e5370a1 SHA-256: 3ccb3720cf1ea10f3473577edbce109b369fbd5b3acf0c337988f95d2b3a2339
194 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to redirect users to potentially harmful content. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, and the presence of embedded URLs points towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://leonvi.ru/award?keyword=refraction+of+light+through+prism+pdf PDF link annotation
    • https://cdn.sqhk.co/xijogedobu/ih99gcn/latest_viral_videos.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4472760/normal_5fc7e05c36792.pdfIn PDF document text
    • http://nesobaka9.xyz/equivalencias_de_unidades_sistema_inglescfqtf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365621/normal_604a488e21009.pdfIn PDF document text
    • https://cdn.sqhk.co/budajawisore/QajdhhH/gatolijobifadunu.pdfIn PDF document text
    • http://osmosiotzs.fun/mini_dv_camcorder_for_sale_los_angelesc4ia0.pdfIn PDF document text
    • http://card2card-perevod24.site/3733890787751oin.pdfIn PDF document text
    • https://cdn.sqhk.co/bemoranoz/ghOhbGs/27889136021.pdfIn PDF document text
    • https://cdn.sqhk.co/xubuzivo/fuRYdMI/zemosujoxebemovawi.pdfIn PDF document text
    • http://realnoe-obshenie.online/umweltschutzgesetz_deutschland63kuh.pdfIn PDF document text
    • https://monirazosakazux.weebly.com/uploads/1/3/5/3/135316997/8a0bb44aa.pdfIn PDF document text
    • https://cdn.sqhk.co/navimoxa/Ljghqjh/30456066336.pdfIn PDF document text
    • https://cdn.sqhk.co/vagofedewat/eSgCLic/my_boy_free_gba_emulator.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425913/normal_6022275d63c2f.pdfIn PDF document text
    • https://jaxoruxevag.weebly.com/uploads/1/3/1/6/131606876/3070025.pdfIn PDF document text
    • http://klokisik.space/77289191306a6ojx.pdfIn PDF document text
    • https://cdn.sqhk.co/xudadidi/rgcVgj0/magic_charm_word_meaning.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4443326/normal_5fcce7064c313.pdfIn PDF document text
    • https://cdn.sqhk.co/muwitajo/g6alDPK/running_android_on_my_pc.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/fowonaxul/47673885519.pdfIn PDF document text
    • https://s3.amazonaws.com/vonutavekip/wakix.pdfIn PDF document text
    • https://s3.amazonaws.com/sewamos/count_on_me_piano_sheet_music_musescore.pdfIn PDF document text
    • https://s3.amazonaws.com/wibedubosateg/free_printable_school_incident_report_forms.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_off0000ef99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF99 5576 bytes
SHA-256: 17ede3bedd54c8c607684fbe50a9c8f1617a985a5ed05540c9f17a095db5cf10
font_01_sfnt_off00010268.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10268 11064 bytes
SHA-256: c54dbd36015f6052ace162db68c8299146265c18256a102c78529bd8c04a8f6d