Malicious PDF — malware analysis report

Static analysis result for SHA-256 77fef11a4fb71dc0…

MALICIOUS

PDF

76.4 KB Created: 2021-02-21 22:40:42 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: d39438e1d55683b24ae3074b48d25944 SHA-1: 54486e8fb30886b25baff9d805c70332babb0f67 SHA-256: 77fef11a4fb71dc001a95081e200833a8846c5357a5ae989b2a386e436a2f016
184 Risk Score

Malware Insights

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

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 and routes users through malicious redirector infrastructure. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 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.
  • 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=imperio+espa%25C3%25B1ol+sin+complejos In PDF document text
    • http://bigno.space/prison_break_season_1_cast_black_womann5bas.pdfIn PDF document text
    • http://white-x.fun/xulikekiwadamiragubizud99vet.pdfIn PDF document text
    • http://rumagadoli.22web.org/bexojegimeropupuse.pdfIn PDF document text
    • http://sdfsdfsdf.shaketorch.com/adobe_reader_10_free_offline_setup.pdfIn PDF document text
    • http://letilemugemin.66ghz.com/58718310915.pdfIn PDF document text
    • http://requiremcgood.com/the_winter_of_our_discontent_summaryct0nm.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://jezawijevot.rf.gd/46474981839.pdfIn PDF document text
    • http://jozeratajugik.rf.gd/lodish_biologia_celular_y_molecular_7ma_edicion.pdfIn PDF document text
    • https://s3.amazonaws.com/bulujono/nolenekogopodifaburi.pdfIn PDF document text
    • https://s3.amazonaws.com/nitatotol/free_bass_guitar_tuner.pdfIn PDF document text
    • http://tapanowi.epizy.com/ipl_2019_file.pdfIn PDF document text
    • http://rowurujo.epizy.com/how_to_fix_a_dewalt_battery_that_wont_charge.pdfIn PDF document text
    • https://s3.amazonaws.com/zufaxepixiguxax/stockholders_deficit_balance_sheet.pdfIn PDF document text
    • http://fewebife.rf.gd/zamenabedupigu.pdfIn PDF document text
    • http://xirugole.epizy.com/lewis_structure_for_co2_with_formal_charges.pdfIn PDF document text
    • http://kisezemewarajox.rf.gd/bolad.pdfIn PDF document text
    • http://podijasopasul.epizy.com/beats_solo_3_cnet_review.pdfIn PDF document text
    • http://xudazefujigi.rf.gd/kasuvufikovabebexufukarob.pdfIn PDF document text
    • http://gonidiwofove.epizy.com/speakeasy_austin_yelp.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_off0000ea7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA7D 5304 bytes
SHA-256: 5a047ecb555908b9085a8899174de37209a3017e67c5836cbd0a4eda0e433e52
font_01_sfnt_off0000fc2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC2A 11988 bytes
SHA-256: cc7d3fd5526ea7c7a9cb4899220e3c26f371adaba7d61ada7ef0f544db394485