Malicious PDF — malware analysis report

Static analysis result for SHA-256 9d8fce78cfcbe2cf…

MALICIOUS

PDF

78.6 KB Created: 2021-05-01 12:33:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 23b77bf1660dda7f16516d23dddf95bb SHA-1: 4fd14918d8a087909cadb2e9abe7fb39a3156824 SHA-256: 9d8fce78cfcbe2cfb6f5db0d04a50da36e3f4df9cbffa6f52319bfaad669056c
252 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains numerous embedded links, many pointing to disposable domains, and one specifically redirects to a known malicious infrastructure. The heuristic 'SE_INVOICE_LURE' suggests the document's content is designed to trick the user into clicking these links, likely to download a secondary payload. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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
  • 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.
  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://crophysi.ru/strik?utm_term=what+is+a+contract+lawyer In PDF document text
    • http://toolsbestpricemicrometer.site/39609769025mufit.pdfIn PDF document text
    • https://cdn.sqhk.co/donewipimep/ihnetgi/woodcutting_3d_simulator_game.pdfIn PDF document text
    • https://nefarixuk.weebly.com/uploads/1/3/1/4/131407944/eddaa497c17850f.pdfIn PDF document text
    • http://zhk-samolet-krasnodar.info/sixedogiwuluwispm02m.pdfIn PDF document text
    • https://cdn.sqhk.co/widiroje/ijgdeY6/60318048907.pdfIn PDF document text
    • https://rupimobo.weebly.com/uploads/1/3/4/8/134891389/633ac46.pdfIn PDF document text
    • http://tehnikator.ru/acurite_14.5_timex_set_and_forget_wall_clockrrl4g.pdfIn PDF document text
    • https://cdn.sqhk.co/bezakebijuk/jh3DBhd/giwex.pdfIn PDF document text
    • http://world-wildshop.com/293789195435lyuu.pdfIn PDF document text
    • https://sagelaxun.weebly.com/uploads/1/3/4/5/134594749/8673830.pdfIn PDF document text
    • https://jijiwunidagaba.weebly.com/uploads/1/3/5/9/135964504/xakadoniwel.pdfIn PDF document text
    • http://mrshadow.net/action_verbs_vocabulary_matching_worksheet_107ajp.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://926da24b-d3df-4aea-ac1b-ebdf7359a9e7.filesusr.com/ugd/fef925_9460522579bc44f0a8929ccd4fdb7351.pdf?index=trueIn PDF document text
    • https://cf176ec6-4820-456b-adf9-61e5f06c968f.filesusr.com/ugd/43d598_3688afaba31f416fb6fddb20e8e3d91a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/5720ba65-1a5b-460e-8bc4-4c913a77f0b9/17195959116.pdfIn PDF document text
    • https://14da0a27-f261-4d4b-8668-3a369f5c966d.filesusr.com/ugd/46429b_e54ce116850f47e1b6f8c2e83c1006b6.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1ce28bd4-c15a-4716-8c6b-32abecea4ed3/what_is_bitcoin_verification_on_cash_app.pdfIn PDF document text
    • https://e209d09f-5af8-48a0-acfc-72d03e9bea0d.filesusr.com/ugd/946fcc_2a5e807dd4bc4e6ead8627e50da24867.pdf?index=trueIn PDF document text
    • https://fa53e508-d88d-41cb-897c-7a5b6f1bfcc3.filesusr.com/ugd/361045_0a4311cbdc8b43efa77d13b89292588b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/ee86b22e-61e7-46e1-94b6-2e9c4cbcf765/82200466711.pdfIn PDF document text
    • https://4fbc56e1-d9a2-4996-be1d-38f9cd263936.filesusr.com/ugd/b1afee_7dddff545dbf48b6984ab482d6c6e6b8.pdf?index=trueIn PDF document text
    • https://3568ea06-17fa-4787-91ae-86b9aa918cbd.filesusr.com/ugd/8ade13_34b4a19917444fe59f2115a34aeeb64f.pdf?index=trueIn PDF document text
    • https://c3438639-6a75-4920-aa4f-d1e0b619354f.filesusr.com/ugd/3be3a7_9051abdb11f1452899d157f78beb7529.pdf?index=trueIn 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_off0000f563.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF563 5096 bytes
SHA-256: c646742dfbd9e2feb5248e304e482c7249cd0837d745c00a8a22dd321b8304cd
font_01_sfnt_off000106cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106CC 10696 bytes
SHA-256: e16d26206113bb6831d6cff1c198296ed3079a3ce91ec4420b0515e4b8ee111f