Malicious PDF — malware analysis report

Static analysis result for SHA-256 535499bf9e831764…

MALICIOUS

PDF

77.0 KB Created: 2021-03-15 06:30:46 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-20
MD5: 01404cb074dd849826c8702a32f5831a SHA-1: 7015e70aef4ab12227b1ba684cb3f8fe907b935b SHA-256: 535499bf9e83176484ab588fb8a47a319cb4543a63fb7ef6897635ee421400e1
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 hosted on disposable domains, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and numerous external URLs point towards a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • 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 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://jacksth.ru/123?utm_term=chernobyl++free+hbo PDF link annotation
    • https://gaxasexafarud.weebly.com/uploads/1/3/4/5/134590452/7321118.pdfIn PDF document text
    • https://nulivuxod.weebly.com/uploads/1/3/0/7/130776854/6860380.pdfIn PDF document text
    • https://cdn.sqhk.co/vafegijateno/jfVhehb/zombie_tsunami_hack_tool_apk.pdfIn PDF document text
    • https://cdn.sqhk.co/sabimejuka/ijjfiiz/dream_racing_experience_las_vegas_coupon.pdfIn PDF document text
    • https://cdn.sqhk.co/sozodumupof/NYjjjdi/draftkings_masters_pool.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4482645/normal_60438839c791b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4418781/normal_5fe5d7425c0b1.pdfIn PDF document text
    • https://cdn.sqhk.co/gapekozuwa/egj928k/strategy_profile_test.pdfIn PDF document text
    • https://risimukino.weebly.com/uploads/1/3/1/3/131383953/sibanoseza_pobili_dokanapar.pdfIn PDF document text
    • https://cdn.sqhk.co/jojojidatun/hLijgca/dragon_war_boom_tycoon_mod_apk.pdfIn PDF document text
    • http://bunnygummy.ru/structure_of_hno3g86el.pdfIn PDF document text
    • http://itravelgr.com/what_is_tcp_ip_explain_the_tcp_ip_model_layers_work_in_hindiudoj9.pdfIn PDF document text
    • https://cdn.sqhk.co/vipujitebiki/ggWUZjf/jomozoxebinurip.pdfIn PDF document text
    • https://cdn.sqhk.co/kolusugego/ify8Oij/bubble_tea_popularity_statistics_singapore.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417205/normal_604ec41c31883.pdfIn PDF document text
    • https://cdn.sqhk.co/wetewajaba/idhjkbT/jazz_call_packages_super_duper_plus.pdfIn PDF document text
    • https://cdn.sqhk.co/lekusovu/hiaJegj/invitational_counter_sniper_team_competition.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://43081b45-6e48-4b43-b724-9328fda377ae.filesusr.com/ugd/26481d_0c20be67980b48298046e01c534165e7.pdf?index=trueIn PDF document text
    • https://f26e6bca-ce10-4524-9610-ed5ef7c8d48b.filesusr.com/ugd/ac8c68_afa2beb6e1e74b2fb768042d7db31d36.pdf?index=trueIn PDF document text
    • https://67a4337f-2b79-4d04-9c1d-2578c80f4945.filesusr.com/ugd/964009_988cd14be5854f6288afde1c0209a39b.pdf?index=trueIn PDF document text
    • https://964beff5-d24f-450a-94e2-fa7e9faef44a.filesusr.com/ugd/61158f_624d3609a94d413e96c7aaae599ce1f5.pdf?index=trueIn PDF document text
    • https://28481333-1ef2-46fb-8ebf-d56c3f24acbc.filesusr.com/ugd/314c35_a2875294c9ab4843aea8af3ae238485c.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_off0000f20b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF20B 4612 bytes
SHA-256: 60cfbc0f6291f8bf40b68c5fc610f9528ba2434cc556fa6662c2df1959dc3cd6
font_01_sfnt_off000101ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101BA 11128 bytes
SHA-256: db8d9bb4fc22075e222374dccf1310763c1dbf2d91aa02603e3fcd14067ff57a