Malicious PDF — malware analysis report

Static analysis result for SHA-256 73fd4855dfc9cc3d…

MALICIOUS

PDF

78.8 KB Created: 2021-03-12 00:35:09 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-04
MD5: 118d9a65ceb3e9222215e8063aa4bb2a SHA-1: 10a021b3ddc1d40d26afe0fecca6960aef557e35 SHA-256: 73fd4855dfc9cc3d13a967fbc681e7667e1282ecf91672ed717ff1eda79583cf
194 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting, indicating a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to phishing or malware sites. While no scripts were extracted, the PDF structure and URL findings are sufficient to classify this as a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://resalured.ru/award?keyword=cholecystitis+pdf+2020 PDF link annotation
    • https://cdn.sqhk.co/kobewudojuvo/i3mNhad/63027350571.pdfIn PDF document text
    • http://matizaw.mywebcommunity.org/34353160481.pdfIn PDF document text
    • http://pifanaliriwabo.mygamesonline.org/adding_decimals_worksheet_vertical.pdfIn PDF document text
    • https://cdn.sqhk.co/nubowolimit/geJibja/99650432124.pdfIn PDF document text
    • http://jarevine.mywebcommunity.org/digamutexijekagenewijidon.pdfIn PDF document text
    • https://cdn.sqhk.co/pidikuso/jRgcjfR/19193355371.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/f5483c40-1d10-42e7-a115-450a1f17b8ca/82870053122.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/290ca6b8-7dd8-4cac-b3aa-c6bcea48b1f0/whats_the_difference_between_hero_7_white_silver_and_black.pdfIn PDF document text
    • https://0503187d-52cd-4237-9521-a3cb9bf551ae.filesusr.com/ugd/5bb01c_19f41ee444734afbbda7da867fd01f87.pdf?index=trueIn PDF document text
    • https://dd907c4b-492b-4b4d-bf3c-9f0b7a2bd2c7.filesusr.com/ugd/96a426_feb63590733646de82ad6f6f5725600a.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/godoremitiwuja/37986775706.pdfIn PDF document text
    • https://8eefcaf3-52f5-4123-8be5-b1f0aaeea45e.filesusr.com/ugd/1d3654_cc4d85c44be142d6aac49b3b1f4eef48.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/3968ae89-4000-4ff5-9252-5e90e5bc3bd1/zepafoziraxelikibasas.pdfIn PDF document text
    • https://s3.amazonaws.com/turip/buried_2010_full_movie.pdfIn PDF document text
    • https://968bac2e-1409-45a7-bd11-2c37eba47390.filesusr.com/ugd/c81504_4872d4016cc64288b1eb9bade9563001.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/eb1e6490-3d0a-43c4-b38a-4c1514e8ecb6/behaviour_support_plan_template_victoria.pdfIn PDF document text
    • https://7d6e376e-1ee3-4df5-88c1-8d1511d419f8.filesusr.com/ugd/7dd30d_c39de6a1fe8249ddadc41f058b3285e4.pdf?index=trueIn PDF document text
    • https://8f1ef4f7-3f23-41ef-a3d6-4e5873a175a2.filesusr.com/ugd/d318ce_40b6efb1965e4538b0bdb70f7888fa98.pdf?index=trueIn PDF document text
    • https://63aa7d51-6c54-48cc-ac87-b710a0da19c3.filesusr.com/ugd/c8d394_51a5e2ff87c74bc8823a032625e34b66.pdf?index=trueIn PDF document text
    • http://manosotidokef.myartsonline.com/lexav.pdfIn PDF document text
    • https://s3.amazonaws.com/vabemavuputenif/66925560571.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_off0000f80c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF80C 5216 bytes
SHA-256: 8f82035ba2127d02226d1b953ea7bbdc9edbcfbbf470cb7cafec28a7ef4daaeb
font_01_sfnt_off000109df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109DF 10720 bytes
SHA-256: 10800434965c19b710fd6f1f6c146ed6fa53536bcfb2cb3e5f45fffb454a6263