Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ef23568355cf41d…

MALICIOUS

PDF

100.0 KB Created: 2021-03-21 22:40:10 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 2c1f5ec9f12b09f7e5df65af8ca25dca SHA-1: 5a3e811a81fa7a6b28db4d6bd1ba05349d6123af SHA-256: 4ef23568355cf41d23352a82dfbf79e64fd20269cfd651fa87f8dc792950a21f
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, indicating a link farm or SEO manipulation scheme. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of malicious activity, potentially involving embedded JavaScript to facilitate redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://leonvi.ru/123?utm_term=ammonium+acetate+solubility+in+chloroform PDF link annotation
    • http://gufutaca3.xyz/tavefeweyffoo.pdfIn PDF document text
    • http://complerbnp.com/fepafovajidonudezufixubo7mijx.pdfIn PDF document text
    • http://lnstagaram-verifiedbadges-from.com/83509120102wwcy4.pdfIn PDF document text
    • https://bigimegena.weebly.com/uploads/1/3/1/4/131438437/xerogan_tebipunodovorej_nixosu.pdfIn PDF document text
    • http://axacheat4.xyz/dungeons_and_dragons_starter_set_rules0huuw.pdfIn PDF document text
    • https://gojesewemuvi.weebly.com/uploads/1/3/2/6/132681304/gafixeg.pdfIn PDF document text
    • https://figuzejigof.weebly.com/uploads/1/3/4/6/134644002/1974615.pdfIn PDF document text
    • https://rizomoxus.weebly.com/uploads/1/3/4/5/134589692/1968724.pdfIn PDF document text
    • http://baffer-shop.space/modunaxeluwzo5re.pdfIn PDF document text
    • https://kevewejisarugi.weebly.com/uploads/1/3/4/6/134611403/6e07d7395dd.pdfIn PDF document text
    • https://vurerabekude.weebly.com/uploads/1/3/4/4/134493837/af2d41c08c9.pdfIn PDF document text
    • https://tiguziriwisil.weebly.com/uploads/1/3/1/0/131071210/2339507.pdfIn PDF document text
    • http://venira.su/easy_learning_german_grammarttboz.pdfIn PDF document text
    • http://flymoney.net/cell_dbz_1st_form5iqrt.pdfIn PDF document text
    • https://gefidiwe.weebly.com/uploads/1/3/0/7/130738847/zaxazez_pivoz_vevupiripuva.pdfIn PDF document text
    • https://warejavusa.weebly.com/uploads/1/3/4/0/134017768/gowuxazewutekokaz.pdfIn PDF document text
    • https://xedagiwaki.weebly.com/uploads/1/3/1/8/131856626/57027.pdfIn PDF document text
    • http://revershjtb.site/ntpc_annual_report_2018-_19zs33f.pdfIn PDF document text
    • https://sezokifor.weebly.com/uploads/1/3/4/5/134596047/3713067.pdfIn PDF document text
    • https://lefoteliwe.weebly.com/uploads/1/3/4/0/134095852/b155b868126b1d.pdfIn PDF document text
    • https://niritopep.weebly.com/uploads/1/3/4/6/134634222/zitibakejapasowile.pdfIn PDF document text
    • http://inmyshtangen.xyz/how_to_register_canon_camera_warranty_onlineffpkl.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/kavalukato/marvel_future_fight_uniform_upgrade_guide.pdfIn PDF document text
    • https://s3.amazonaws.com/gedexim/how_to_connect_google_mini_to_iphone.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013235.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13235 5352 bytes
SHA-256: 59677dc58bf15c535b496a89ad8de587de782bc907b5cb3619981cfd24973719
font_01_sfnt_off00014443.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14443 11276 bytes
SHA-256: d482cf2a5dac92dbc237dfd7b26e72b6d35a3419a5e21e471fc3b29e017e1af8
font_02_sfnt_off00016ab0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16AB0 16628 bytes
SHA-256: b822b9f77a7a7284805bd6494fafb2126acf356931ac47459110897157775b97