Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b68ef4f0dff9efb…

MALICIOUS

PDF

77.1 KB Created: 2021-03-21 04:33:03 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3f02b3c632a36a509f7a858902fd3c48 SHA-1: aca2eddefde96bbd034c7b4f1875849ea9d28d6d SHA-256: 1b68ef4f0dff9efb85048f93ebc87a6f365867e6500d7ba59849d0d7589cd704
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, with a critical heuristic identifying it as a link farm. One prominent URL, 'https://dafemum.ru/wix?keyword=teas+study+manual+free', is presented as a 'teas study manual free', suggesting a lure for users. The presence of embedded URLs and a high ML classifier score further support malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 5

  • 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
  • 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://dafemum.ru/wix?keyword=teas+study+manual+free
    • https://cdn.sqhk.co/batitiviz/bjjgigg/8196483914.pdf
    • https://cdn.sqhk.co/zasokolof/hdigrjh/73117636965.pdf
    • https://cdn.sqhk.co/razilipot/gMDjihj/vedezinamexaxirug.pdf
    • https://cdn.sqhk.co/fedefuxu/auieXBP/spoof_call_fake_caller_id_app_download.pdf
    • https://cdn.sqhk.co/zesojesiwi/g1DuHij/maxpreps_athens_ohio_football.pdf
    • https://cdn.sqhk.co/dabozijide/WlhihA0/sniper_shot_2k18_mod_apk.pdf
    • https://cdn.sqhk.co/jumapevuz/fgjgghe/lasamawawotuse.pdf
    • https://cdn.sqhk.co/bogovureg/n1jeOfS/photo_collage_template_indesign.pdf
    • https://cdn.sqhk.co/lizubenesowi/gcihiiz/cat_flipping_the_bird_pic.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/tikofaketonub/smart_goals_tip_sheet.pdf
    • https://c2dbac7f-2075-4dc1-ad03-af0d0352bff2.filesusr.com/ugd/278743_6bd8ed85970641d4a70b0349f01ed149.pdf?index=true
    • https://s3.amazonaws.com/fobupojowojon/5717206156.pdf
    • https://s3.amazonaws.com/wutogugej/jabojupimidadujamuwez.pdf
    • https://s3.amazonaws.com/xuzed/class_dojo_student_login_page.pdf
    • https://7f1888b6-cdab-4603-9914-1cf81a8b29aa.filesusr.com/ugd/6846fe_b39f841361ae436a8020cdd31c000e6a.pdf?index=true
    • https://s3.amazonaws.com/fifuto/physical_properties_of_alkali_metals.pdf
    • https://s3.amazonaws.com/sorogamat/the_global_competitiveness_report_2019.pdf
    • https://s3.amazonaws.com/tugabijenovili/jukoma.pdf
    • https://s3.amazonaws.com/fapaga/how_to_scale_a_race_car.pdf
    • https://s3.amazonaws.com/vipinib/istqb_sample_exam_answers.pdf
    • https://s3.amazonaws.com/gopifu/sense_and_sensibility_streaming_free.pdf
    • https://s3.amazonaws.com/makixibawumebol/afan_oromo_new_music.pdf
    • https://s3.amazonaws.com/sajatesawodiji/63980950377.pdf
    • https://s3.amazonaws.com/muvarelo/does_sonic_still_have_half-price_shakes_after_eight.pdf
    • https://c02a3fa2-970f-4384-b4fa-7a60184a1b73.filesusr.com/ugd/1da3fe_cfcfab00ca3040a3840c53eddced278d.pdf?index=true
    • 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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ef46.bin
73dc46feaa99b959503e2fa5e997cfa4892d11bdbc76000aad2bd83ff9adaecf
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF46 5104 bytes
font_01_sfnt_off00010094.bin
f83e1d95291c749db0a053ca0f0dced1184654db6b22c1546dc3fbde363c133c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10094 11204 bytes