Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc1a4a4b4f7a5f45…

MALICIOUS

PDF

86.8 KB Created: 2021-03-04 22:49:22 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 030bbd86635d99b76e603a8e5ff7caee SHA-1: 923ed9742729019b691b7591f59cf66ea3822ec1 SHA-256: bc1a4a4b4f7a5f4520188be1b2f4b58400ad850c0f9d4b187bfc901e77ceb54c
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or phishing lure. ClamAV and ML classifiers strongly indicate maliciousness, with the PDF_SEO_LINK_FARM heuristic specifically identifying the mass linking behavior. No scripts were extracted, but the primary attack pattern involves redirecting users to potentially malicious external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://nipisod.ru/award?keyword=systemverilog+interface+definition PDF link annotation
    • https://pegugigatusib.weebly.com/uploads/1/3/4/4/134460290/wanari.pdfIn PDF document text
    • http://tepugorotewole.medianewsonline.com/79435442567.pdfIn PDF document text
    • https://minezutoka.weebly.com/uploads/1/3/2/6/132695516/wekugoletal_vexadapu_zalerexuv_giluvamis.pdfIn PDF document text
    • http://jazulivorif.iblogger.org/jurnal_keanekaragaman_bivalvia.pdfIn PDF document text
    • http://graatorama.space/tavutajozejugeposap37akf.pdfIn PDF document text
    • http://lomigakorak.getenjoyment.net/kavesujebezuduwubex.pdfIn PDF document text
    • http://amsidisi.xyz/2635440943daq69.pdfIn PDF document text
    • https://watagejikifawup.weebly.com/uploads/1/3/4/5/134589749/futigizuzujaja.pdfIn PDF document text
    • https://wusuritod.weebly.com/uploads/1/3/0/7/130739885/dafunalibim.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://f5711562-8a0d-4a87-802d-80b49b7e2cae.filesusr.com/ugd/455f95_b5461ad790e1425e93118c2419f90670.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/aae0da77-d613-4bd1-84fb-6458fded145a/49759873312.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/69b97dcb-5ef7-48c3-a861-4de32ae2248e/22722316773.pdfIn PDF document text
    • https://587b455d-cc79-4428-8e80-a8b75ce23bca.filesusr.com/ugd/021ec8_ad1095c1f3d64d929004ad2eb0d7b534.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/86301ca9-f143-409f-8646-893f1983ee29/wolf_oven_cleaning_manual.pdfIn PDF document text
    • https://00407fa8-a9ef-4b78-9bbe-46147fc8acf6.filesusr.com/ugd/5ecadc_93db373b41b24bff87b7cc7522b1b0e2.pdf?index=trueIn PDF document text
    • http://wizifaj.rf.gd/gelelazekabukosi.pdfIn PDF document text
    • http://tixerewolulas.rf.gd/dedufesixevimopenagi.pdfIn PDF document text
    • http://giratas.epizy.com/aphis_7001_continuation_sheet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d2806b8e-adec-4c89-abc5-f6c740665628/blender_2.8_tutorial_deutsch.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000108ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108AC 5392 bytes
SHA-256: 5185b58453cf607c5c37147aff95f63fd805c3f212f81aedac3ae9b901499a1c
font_01_sfnt_off00011aed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AED 10920 bytes
SHA-256: cc745182e36bd440a8e83bdaeb016f7f438405b47e8eedc5cda89f81a2552473
font_02_sfnt_off00014015.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14015 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176