Malicious PDF — malware analysis report

Static analysis result for SHA-256 352315f82a04ef2e…

MALICIOUS

PDF

72.6 KB Created: 2021-03-14 14:23:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 27b3199d39c54ab223db7df0abc4d697 SHA-1: 7ca3e3821790518abd7d07f128de4671a55ad2f3 SHA-256: 352315f82a04ef2e2e007ec39b02588e46756e74ba9c3f941f4bcc74122549e2
252 Risk Score

Malware Insights

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

The sample was flagged by multiple critical heuristics, including PDF_MALICIOUS_REDIRECTOR_LINK and PDF_SEO_LINK_FARM, indicating it functions as a link farm. The embedded URLs point to suspicious domains, and the ML classifier strongly suggests malicious intent. The document's purpose appears to be directing users to potentially harmful content or further stages of an attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 7

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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 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
  • 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://yafferge.ru/wix?keyword=kaplan+pcat+pdf
    • https://static.s123-cdn-static.com/uploads/4486981/normal_5fc85cd1032de.pdf
    • http://helplnstagramcontact6088758.com/motogp_racing_17_championship_mod_apk_revdlnbhnp.pdf
    • https://mozevosiku.weebly.com/uploads/1/3/3/9/133999333/210418.pdf
    • https://cdn-cms.f-static.net/uploads/4466161/normal_600f2970a5c14.pdf
    • https://zalozudipob.weebly.com/uploads/1/3/4/6/134673455/155d0c2760.pdf
    • http://organicnu.info/movado_series_800_rubber_strap_replacementlu08g.pdf
    • https://ketowijogi.weebly.com/uploads/1/3/5/9/135985413/sanobizimukedufatu.pdf
    • https://cdn-cms.f-static.net/uploads/4461751/normal_60126c2fbd838.pdf
    • https://cdn.sqhk.co/pubamegumox/hnYiigh/hands_cramping_when_sleeping.pdf
    • https://jafukixago.weebly.com/uploads/1/3/1/3/131380625/xivetinilejipikarira.pdf
    • https://cdn-cms.f-static.net/uploads/4465252/normal_60366779536c0.pdf
    • https://cdn.sqhk.co/kufalavoxig/2igiLhe/6357708317.pdf
    • https://xakebugus.weebly.com/uploads/1/3/4/0/134018628/8751433.pdf
    • https://static.s123-cdn-static.com/uploads/4405440/normal_5fc9e00e72e21.pdf
    • https://cdn.sqhk.co/vumuwilaj/jg7PILQ/ginekezotaxilev.pdf
    • https://cdn.sqhk.co/luginuwi/ibhb9ji/97342644822.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://6c036dbd-b327-4678-b778-de8a2ee7bb50.filesusr.com/ugd/ed64d2_98adca914d1c4e5b9a18daff0eadf463.pdf?index=true
    • https://uploads.strikinglycdn.com/files/93c49d6b-b092-440d-8d1f-e8dbe855908c/celestron_astromaster_90_review.pdf
    • https://469ee322-798e-4c1d-9571-af6764901f97.filesusr.com/ugd/57169b_2d7b14ad62164cccb200f0e7d0e6811e.pdf?index=true
    • https://143c7e3e-1a56-4739-9c24-5aac26b0263b.filesusr.com/ugd/28d7c1_7a228dd3b4b845c3bab993bc54b97169.pdf?index=true
    • https://uploads.strikinglycdn.com/files/5902e55e-7a1f-428b-8bc4-b578e2ae21e5/12522783133.pdf
    • https://uploads.strikinglycdn.com/files/e876edb9-e2b1-4a79-b655-73dad7fee90d/lee_hammonds_all_new_big_book_of_drawing_beginners_guide_to_realistic_drawing_techniques.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dfb0.bin
5a6ff22338a2cdafc0cbb15917eb3eee8509e4da7efd77a26a59171fce0e211e
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFB0 4844 bytes
font_01_sfnt_off0000f049.bin
89a9056cf7e89bfd39164e17ff20cb95245b35a749204e9aff833c7eca3a42cd
pdf-font-stream PDF embedded font (sfnt) at offset 0xF049 11112 bytes