Malicious PDF — malware analysis report

Static analysis result for SHA-256 39b7c2e862e162a9…

MALICIOUS

PDF

85.1 KB Created: 2021-03-08 05:34:04 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-07
MD5: 31bdb292b360dc6fef833df30a7fa08c SHA-1: 5ec693959f330e37c7c85573a39320c1e0bd27c1 SHA-256: 39b7c2e862e162a9c762e52d720c84373de5f3a02acba8e019d7f6ab6292aa4e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious content. It contains numerous embedded URLs, with several pointing to suspicious domains and one identified as a link farm on disposable hosting. The document body, though heavily obfuscated, appears to be a lure related to job candidate questions, likely intended to drive users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://nipisod.ru/strik?utm_term=questions+to+ask+a+management+job+candidate PDF link annotation
    • http://jaxagogilexet.sportsontheweb.net/rabanuguxufel.pdfIn PDF document text
    • http://nitanupemil.mygamesonline.org/rujizozi.pdfIn PDF document text
    • http://walifekatude.iblogger.org/32679833672.pdfIn PDF document text
    • http://salea.site/22206995058o1jfh.pdfIn PDF document text
    • http://kemytbok.xyz/122230664549d17n.pdfIn PDF document text
    • http://instapriz.online/should_i_buy_a_sub_zero_refrigerator92ob5.pdfIn PDF document text
    • http://remont-kvartir-otzyvy.moscow/tulijikitinobyrw6a.pdfIn PDF document text
    • http://konalofasu.mywebcommunity.org/ti_nspire_cx_games_pokemon_download.pdfIn PDF document text
    • http://sozaxesugoj.mywebcommunity.org/mixed_up_files_of_mrs_basil_e_frankweiler_chapter_summaries.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/a14ad331-57b7-4aef-ba52-6ad13d9cd3b5/should_between_be_capitalized_in_a_title.pdfIn PDF document text
    • https://bc5ba30c-e427-49eb-abc4-9677f18f04c1.filesusr.com/ugd/bcd086_adb52ad0c9644dda8a1405e23f7ce1f5.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/99a67e87-c13e-458b-9832-667c8d80d2c3/best_side_by_side_1000cc.pdfIn PDF document text
    • https://944456f3-75eb-4cd6-bbfd-656b3713ada1.filesusr.com/ugd/2c8d66_e52ca1b733084955849afc31539c4788.pdf?index=trueIn PDF document text
    • http://rolubumemetujin.atwebpages.com/fokawowimo.pdfIn PDF document text
    • https://ac3db616-04cb-40f1-8357-c67041f5e20c.filesusr.com/ugd/eda9ba_fe56ccf10f314fa1bbbe1282f0a3f794.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1608d2f2-91f7-4ed6-b9b9-e4f905609441/84431915498.pdfIn PDF document text
    • https://ca30e0e0-ecf2-44ab-b6a2-fe26291458be.filesusr.com/ugd/34e21e_0307061db58a4245868a26d376f4a5b2.pdf?index=trueIn PDF document text
    • http://kufilabed.epizy.com/sofasalulanisebox.pdfIn PDF document text
    • http://gidatefasu.rf.gd/ordeal_by_cheque_short_story.pdfIn PDF document text
    • http://jokubamobivavum.onlinewebshop.net/how_much_are_the_infinity_gauntlet_comics_worth.pdfIn PDF document text
    • http://vekoxoke.epizy.com/editable_shadowrun_5_character_sheet.pdfIn PDF document text
    • http://tuxefunuzire.atwebpages.com/sanborn_magna_force_air_compressor_2hp.pdfIn PDF document text
    • https://a1d3e036-d9a1-4be1-9d2f-eedbb581cb22.filesusr.com/ugd/3ce946_d150d5873008417493fd76438627259a.pdf?index=trueIn 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_off0001116c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1116C 5472 bytes
SHA-256: ad8e7df05a1318d3e9d37b4d52cdd0a39defdb94841e527f4f95d2efa3ad5ba3
font_01_sfnt_off00012402.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12402 10300 bytes
SHA-256: ad3f658cfad79ba647b04ff2fa7980627d5fce9ed83b304f8fcbcd5ac2a22443