Malicious PDF — malware analysis report

Static analysis result for SHA-256 539962ba5e2dbd18…

MALICIOUS

PDF

84.2 KB Created: 2021-03-15 23:26:47 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 3a4940c5fe638345f88722536c92f20a SHA-1: 5b20bb279194e361da4e720b3dcefe0d69c0ccde SHA-256: 539962ba5e2dbd18adad17dff85aa6f59b806e7a8cd78ee4ae02d91b7577b53a
156 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 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
  • 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.
  • 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://jacksth.ru/award?keyword=acretismo+placentario+por+ultrasonido+pdf PDF link annotation
    • https://birobidusizal.weebly.com/uploads/1/3/4/6/134638138/melif.pdfIn PDF document text
    • http://uscreditcheck.info/ninestars_garbage_can_replacement_lid5re5s.pdfIn PDF document text
    • https://zopodiwozexuma.weebly.com/uploads/1/3/4/7/134737972/6535484.pdfIn PDF document text
    • http://stankoff.org/delta_math_answers_geometryjho23.pdfIn PDF document text
    • http://siankaanmexico.com/basic_electrical_and_electronics_engineering_solved_problemsy4tkc.pdfIn PDF document text
    • http://koreanluxe.com/bouncy_chair_babyoshyf.pdfIn PDF document text
    • http://kkkirrreeee.space/idate_commission_reportr9k8l.pdfIn PDF document text
    • https://tulalesin.weebly.com/uploads/1/3/4/8/134876190/6870260.pdfIn PDF document text
    • http://btsworld.org/what_is_the_rising_sun_flag_mean0iibu.pdfIn PDF document text
    • https://duxuremi.weebly.com/uploads/1/3/4/6/134623812/5729136.pdfIn PDF document text
    • https://suzagosezamonu.weebly.com/uploads/1/3/4/4/134446802/5436162.pdfIn PDF document text
    • http://wisecredit.info/tozevabebavifogopofurileg9rwxh.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/wizedumi/pujojolusovugigipixod.pdfIn PDF document text
    • https://s3.amazonaws.com/mutirexa/clr_via_c_4th_edition_developer_reference.pdfIn PDF document text
    • https://s3.amazonaws.com/muwomapotumugi/how_do_you_simplify_radicals_with_exponents.pdfIn PDF document text
    • https://s3.amazonaws.com/mivokozibu/70526959630.pdfIn PDF document text
    • https://s3.amazonaws.com/tiluwisulepam/89808896799.pdfIn PDF document text
    • https://s3.amazonaws.com/vinivuxo/sims_freeplay_app_cheats_android.pdfIn PDF document text
    • https://s3.amazonaws.com/dorobukasawituw/collision_reporting_centre_kitchener_waterloo.pdfIn PDF document text
    • https://s3.amazonaws.com/bulolimepol/bacteria_and_virus_worksheet.pdfIn PDF document text
    • https://s3.amazonaws.com/juvuraguvutoxif/employee_compensation_policy_template.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_off00010b4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B4B 5288 bytes
SHA-256: 77e1c36b1a4c97b1dcf469f4db2825931519fc53620af82936f4c0a6a78da50b
font_01_sfnt_off00011d31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D31 11700 bytes
SHA-256: 2cb2982cb30adc90102cacbf03107222721eb7498d22887a651f26417ae262f6