Malicious PDF — malware analysis report

Static analysis result for SHA-256 91ed455d3fc1ef47…

MALICIOUS

PDF

80.5 KB Created: 2021-03-06 19:52:58 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fe54e801d8b0ecaaa8e30c4934889591 SHA-1: 1897cf28b48379ee9dff995bda6946be2ae565e8 SHA-256: 91ed455d3fc1ef47f16f3879105433d855224b041650df0068fb4bc5a2f561cf
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and embedded URLs point towards a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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://botokaw.ru/strik?utm_term=what+is+the+woodcock+johnson+test+of+cognitive+abilities
    • https://cdn.sqhk.co/nalomuxe/jhWjjql/yaheetech_modern_simple_design_home_office_desk.pdf
    • https://megopupe.weebly.com/uploads/1/3/1/1/131163834/4651726.pdf
    • https://zizojatemizowen.weebly.com/uploads/1/3/4/0/134016780/gafux_vewefikovos_wolizevux.pdf
    • https://luwujapi.weebly.com/uploads/1/3/4/7/134751522/govutapajepig.pdf
    • https://cdn.sqhk.co/remonupode/Tjgv5ij/sailor_cats_codes_april_2020.pdf
    • https://cdn.sqhk.co/nizivatitogu/kjihYyV/where_are_cashion_fishing_rods_made.pdf
    • https://static.s123-cdn-static.com/uploads/4468831/normal_5fe208ac9036e.pdf
    • https://jepejopik.weebly.com/uploads/1/3/4/6/134610321/ninokifeberuse_wukewavux_dunudixivug.pdf
    • https://cdn.sqhk.co/gufezitaxato/GGGuDjf/58371757520.pdf
    • https://wozijosetat.weebly.com/uploads/1/3/1/4/131407158/kaniwanedamudex.pdf
    • https://cdn-cms.f-static.net/uploads/4445555/normal_603eb663e4025.pdf
    • https://cdn-cms.f-static.net/uploads/4481052/normal_6016a6be7d96d.pdf
    • https://biditojutorosas.weebly.com/uploads/1/3/4/6/134657596/3974113.pdf
    • https://cdn-cms.f-static.net/uploads/4481699/normal_60243ca2966dd.pdf
    • http://pifowovumuwe.medianewsonline.com/como_agua_para_chocolate_translation_to_english.pdf
    • https://mifabawir.weebly.com/uploads/1/3/0/7/130776047/1559137.pdf
    • https://cdn.sqhk.co/woxemumi/cDgjGjc/19069474293.pdf
    • https://dakufosaxem.weebly.com/uploads/1/3/4/7/134771611/1543998.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://s3.amazonaws.com/gotitibekovi/remavubokulazoga.pdf
    • http://faxiruvud.myartsonline.com/fipaxozejowub.pdf
    • https://s3.amazonaws.com/mafavuzenoliki/industrialcraft_2_guide.pdf
    • http://tigagatu.atwebpages.com/best_life_coaching_programs_2020.pdf
    • https://s3.amazonaws.com/tosevud/kuzuxadesaz.pdf
    • https://s3.amazonaws.com/lusegokaves/biremuru.pdf
    • http://sipanokule.onlinewebshop.net/thirteen_reasons_why_best_characters.pdf
    • https://s3.amazonaws.com/wixamupelinere/emulator_for_playing_pc_games_on_android.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ecc9.bin
53b6b3e2002aa26ecdbb643c2e38a9f68e2c446ec65b2c027d2d1a612895c1f3
pdf-font-stream PDF embedded font (sfnt) at offset 0xECC9 5420 bytes
font_01_sfnt_off0000ff54.bin
33a7f06206a2375dd3f3075874b763ffa31b191b8a6d2abab544e9640f270a28
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF54 11476 bytes
font_02_sfnt_off000125b2.bin
a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f
pdf-font-stream PDF embedded font (sfnt) at offset 0x125B2 4324 bytes