Malicious PDF — malware analysis report

Static analysis result for SHA-256 21f0b05a65d58068…

MALICIOUS

PDF

80.0 KB Created: 2021-03-31 03:00:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: eba571697e60da9e4839688589655742 SHA-1: b52d60d08903c075cc0f496019e2957e16fcc745 SHA-256: 21f0b05a65d5806822e278dd475e14128e59f43d933dfeb75eaf2ae8c6253b67
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://mezovuduw.ru/wix?keyword=sorry+we+couldn%2527t+skype+tonight+text+art PDF link annotation
    • https://cdn.sqhk.co/gizoxemovefi/2gchbYn/53503748587.pdfIn PDF document text
    • https://cdn.sqhk.co/budajawisore/bhaghjb/run_rate_calculation_formula_in_ipl.pdfIn PDF document text
    • https://cdn.sqhk.co/joxonorapa/3dLgghe/cut_it_out_scrapbooking.pdfIn PDF document text
    • https://cdn.sqhk.co/mowefakura/vhjTgd5/whatsbluetext_stylish_font_app_download.pdfIn PDF document text
    • https://kubuvapag.weebly.com/uploads/1/3/0/7/130776206/nazim.pdfIn PDF document text
    • https://cdn.sqhk.co/merabuvi/dphivie/air_hockey_ping_pong_table_top.pdfIn PDF document text
    • https://cdn.sqhk.co/sesakiwewe/kgchaje/18962906469.pdfIn PDF document text
    • https://cdn.sqhk.co/mozoposowi/bhdLEW3/summer_camp_staff_training_videos.pdfIn PDF document text
    • https://cdn.sqhk.co/telapunojawu/cgehfib/nufigaloderunejatoxitise.pdfIn PDF document text
    • https://xefanopebowemid.weebly.com/uploads/1/3/2/6/132681782/5523141.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://robosawubu.epizy.com/types_of_thyroid_disorders.pdfIn PDF document text
    • https://e0fa0743-814d-41de-b6a5-47f787911882.filesusr.com/ugd/89d2ef_7f29ac5d46d341da926c2a15ac99d902.pdf?index=trueIn PDF document text
    • https://0e818273-c791-4c7a-b20f-750474b78fe4.filesusr.com/ugd/362633_902751c2145d4228a1fe29ba3d806672.pdf?index=trueIn PDF document text
    • http://dufosulux.epizy.com/calculus_art_of_problem_solving.pdfIn PDF document text
    • http://fuzariwa.rf.gd/payback_period_method_example.pdfIn PDF document text
    • https://393102e6-89af-4738-8cad-89662dba8dc5.filesusr.com/ugd/33a16d_a1d6b63848da426aa0d3b080ee8911b6.pdf?index=trueIn PDF document text
    • https://6131fb9f-3080-406c-a6ab-c4686b6a2f6f.filesusr.com/ugd/52be6f_1dc54d40011c48ca9301b132b33b8864.pdf?index=trueIn PDF document text
    • https://507d1b22-ea03-4061-a262-f79425337ca2.filesusr.com/ugd/a374b9_f6229741981d46d4996033050d0a462f.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d15e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD15E 4808 bytes
SHA-256: 5987147ca01f0a92b86e9b17ce9c9f063800e31245ef40fa58c9ad8ab35fef36
font_01_sfnt_off0000e255.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE255 5800 bytes
SHA-256: 2255cb4fa4dd8e7f594a0801dc5296a0fbaa3a2e9dac644fd7aeebf27dc6c6aa
font_02_sfnt_off0000f631.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF631 10624 bytes
SHA-256: 40f9c1175a8f0412716e178b3025436ecb4ee1c4c50792d290923522468d282e
font_03_sfnt_off00011aeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AEB 16076 bytes
SHA-256: 6b13f8def256235e3ecdb6cd1b4534f0823fff5a25810a35c090d1b32d4fa7c4