Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb7bf9b9c3c1048d…

MALICIOUS

PDF

77.9 KB Created: 2021-04-30 04:05:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7b6e4b187ad2cc10ddb6d47a5be0adaa SHA-1: 9620ef3ee9b8875f4d23e6ee18ee99eb0b853174 SHA-256: bb7bf9b9c3c1048d9273cf3ac379dd5a501614b91ce5459e88b94d66e732ed61
186 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as a link farm and by a machine learning classifier as malicious. It contains numerous external links, many pointing to disposable domains, suggesting an attempt to drive traffic or distribute further malicious content. The ClamAV detection as 'Pdf.Phishing.Trojan' further supports its malicious nature. No scripts were extracted, but the PDF structure itself is used to host and link to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 6

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://seumenha.ru/strik?utm_term=circle+graph+worksheets+4th+grade
    • http://jipolavex.medianewsonline.com/what_not_to_eat_to_get_in_shape.pdf
    • https://cdn.sqhk.co/rasetiwulipu/fhhkgcq/53355965741.pdf
    • https://bujubilefo.weebly.com/uploads/1/3/1/4/131406518/68be2c100ef2.pdf
    • http://gexopidikimo.mygamesonline.org/what_are_the_benefits_of_data_warehousing.pdf
    • https://cdn.sqhk.co/mumeriretepi/g4Ykhca/withings_steel_hr_band.pdf
    • https://cdn.sqhk.co/monasomeb/ggJdVp7/game_call_of_magic_mod_apk_android_1.pdf
    • https://cdn.sqhk.co/fafojipedul/hEsyRff/70665061964.pdf
    • http://vudifabofugejij.medianewsonline.com/how_do_i_access_wd_my_cloud_on_windows_10.pdf
    • https://xabogiseduwa.weebly.com/uploads/1/3/4/7/134717421/866d990613e37.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://03dfb0eb-7fe6-4188-ad87-ea2b88df7b19.filesusr.com/ugd/f967ac_a4256ba617f740eab75e0cddeca09f03.pdf?index=true
    • http://nubibubimalepik.atwebpages.com/ncert_class_12_chemistry_chapter_1_notes.pdf
    • https://4a39c6c9-989b-4d11-b2d8-cc0becc7f193.filesusr.com/ugd/ef0078_b124c3c4a2834a66be8a46da7e14637b.pdf?index=true
    • https://5be7aec3-7d66-433b-ae1d-2bfb807ddf2a.filesusr.com/ugd/24deb6_2d20affaca044cc68511452e2d6be5b8.pdf?index=true
    • https://e714dd98-3e42-4604-aba1-6d4b2506b1a8.filesusr.com/ugd/742965_5b1dd159426042be928668ca289d8164.pdf?index=true
    • https://7aff118d-26f6-4d76-9bc9-1838009e7274.filesusr.com/ugd/f80014_4d28701340234381b6ec349b4151079e.pdf?index=true
    • https://s3.amazonaws.com/gapuruxumeg/how_to_install_ds4_on_windows_10.pdf
    • https://52ed6390-a5c1-4502-9f93-599cf6d98ad1.filesusr.com/ugd/f7fbc8_1165f0a367d64c5c8434f79925646c72.pdf?index=true
    • https://s3.amazonaws.com/padosumifubobo/2118567097.pdf
    • http://zasuwunal.myartsonline.com/neuromancer_william_gibson_mobi.pdf
    • https://959e49da-b405-4961-97d4-5c1bb2e9a628.filesusr.com/ugd/ab0441_5f2230ac65e447df990902fb2d8c6fd7.pdf?index=true
    • https://s3.amazonaws.com/xurixado/employee_complaint_log_excel_template.pdf
    • https://c039f79f-855f-4b64-8838-30138aeea086.filesusr.com/ugd/6b78cb_aaf7c1aaf056474db805c92d0dc30ceb.pdf?index=true
    • https://s3.amazonaws.com/fonibinaraj/3_hp_briggs_and_stratton_engine_manual.pdf
    • https://s3.amazonaws.com/vasofirida/59248760759.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ddf1.bin
76d28baf78f1a84e9b13b03cd642ade409a265809abf7faac6eb44de36819721
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDF1 5484 bytes
font_01_sfnt_off0000f0a9.bin
f40162159a398f524fa362c240ea2177459415accd2c7c5cbe27226c48c1a2e9
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A9 10348 bytes
font_02_sfnt_off00011460.bin
541fa2b6826b0add99b7d5a173ef1e6a5567607b5192f75b810eb17d6a563501
pdf-font-stream PDF embedded font (sfnt) at offset 0x11460 16204 bytes