Malicious PDF — malware analysis report

Static analysis result for SHA-256 befa50945d0dc47d…

MALICIOUS

PDF

78.8 KB Created: 2021-06-04 08:56:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: fc86effa057e0ed55ce466664ecadde1 SHA-1: 2b3f575b7b83c64dfc0201a1a41407e280d7cb01 SHA-256: befa50945d0dc47ddf66dac95cfbcf01d6617fa4b9d3cef4d6ae35b5b79d403b
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with a significant portion pointing to disposable domains and a high number of links per host, indicative of a link farm. One prominent URL, 'https://coretry.ru/pbw?utm_term=graphing+calculator+screen+problems', is flagged as unknown reputation and is likely the primary lure. ClamAV detection and ML classification strongly suggest malicious intent, aligning with a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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 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://coretry.ru/pbw?utm_term=graphing+calculator+screen+problems PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4373504/normal_60b88e0f2f690.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411512/normal_60443f22e640b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4451206/normal_6009084a5355c.pdfIn PDF document text
    • https://gagemixe.weebly.com/uploads/1/3/5/2/135295047/numolevuximo_gotevinepov_wifogejikasiba.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373502/normal_6010c45c11225.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4418963/normal_5fc7036981216.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421330/normal_60537ad5c306c.pdfIn PDF document text
    • https://soputepitup.weebly.com/uploads/1/3/5/9/135973261/zezalizemami_zituzetexanu.pdfIn PDF document text
    • https://sadavixiji.weebly.com/uploads/1/3/5/3/135333995/9739640.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416299/normal_6046395c0fc36.pdfIn PDF document text
    • https://voxuvuru.weebly.com/uploads/1/3/5/3/135390020/6c49f8a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386839/normal_5fd5f0c2a70c5.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://siwuromo.pbworks.com/w/file/fetch/144424752/how_to_mount_a_badland_winch.pdfIn PDF document text
    • http://kepojijudiva.pbworks.com/w/file/fetch/144526398/tere_bin_nahi_jeena_mar_jana_dholna_hindi_songs.pdfIn PDF document text
    • http://xujefix.pbworks.com/w/file/fetch/144576621/teorias_de_la_personalidad_duane_p._schultz.pdfIn PDF document text
    • http://betosaxugawi.pbworks.com/f/10928485278.pdfIn PDF document text
    • http://togiwuvoze.pbworks.com/w/file/fetch/144590253/taliwufikufamamibowanunal.pdfIn PDF document text
    • http://siseraxoru.pbworks.com/f/temilewesiwusum.pdfIn PDF document text
    • http://gatasulupu.pbworks.com/w/file/fetch/144422328/anamorphic_lens_flare_plugin_fcpx.pdfIn PDF document text
    • http://guronavageba.pbworks.com/f/xesarupawogezegiva.pdfIn PDF document text
    • http://kufujibumufa.pbworks.com/f/snow_white_prince_charming.pdfIn PDF document text
    • http://ridelox.pbworks.com/f/galaxy_s_edge_guide_maps.pdfIn PDF document text
    • http://luwivaj.pbworks.com/f/download_bleach_brave_souls_mod_apk_offline.pdfIn PDF document text
    • http://lulimogosan.pbworks.com/w/file/fetch/144510108/android_oyun_club_gta_v_cretsiz_indir.pdfIn PDF document text
    • http://pusavivo.pbworks.com/f/substrate_level_phosphorylation_in_glycolysis.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_off0000df86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF86 5520 bytes
SHA-256: 5cff7e089def0228d730c2b7f28f8d5c189a6d8184a78efb4a0a3fbece1bd066
font_01_sfnt_off0000f21d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF21D 11052 bytes
SHA-256: 8b440db001a6bf5bed921a2eaf0b6574ef158e98679479faa5bf45e57cc22110
font_02_sfnt_off00011817.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11817 16144 bytes
SHA-256: a0532d1212509dae036733b1fb6f303b0d7fd7a209d3928fdad713008da19d30