Malicious PDF — malware analysis report

Static analysis result for SHA-256 20f52e9a4108b821…

MALICIOUS

PDF

70.7 KB Created: 2021-04-06 06:11:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 7d18ec1d523df4f6e54993ba565f4794 SHA-1: 1c295d7e0233e3227a2155a4a192d0b6d1adf548 SHA-256: 20f52e9a4108b82192e815d67b8bbb09e7548b9c4db09e8073daa4ff6fd8201c
186 Risk Score

Malware Insights

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

This PDF file is classified as malicious due to its function as a link farm, directing users to numerous other PDF files hosted on disposable domains. The primary lure appears to be academic content, specifically 'Bsc physics 1st semester question papers pdf', aiming to trick users into downloading further malicious payloads. The ML classifier and ClamAV detection strongly support the malicious nature of this document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • 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 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://resalured.ru/award?keyword=bsc+physics+1st+semester+question+papers+pdf PDF link annotation
    • https://todurudivi.weebly.com/uploads/1/3/4/3/134344361/3661110.pdfIn PDF document text
    • https://zekigoduse.weebly.com/uploads/1/3/4/3/134336209/dikonisitewufekowezi.pdfIn PDF document text
    • https://moxizeza.weebly.com/uploads/1/3/3/9/133999163/gonal.pdfIn PDF document text
    • http://detonic-hypertonie.website/foxit_reader_for_ubuntu_freebxxb8.pdfIn PDF document text
    • http://suwetobolubujub.getenjoyment.net/64841417266.pdfIn PDF document text
    • http://xenejesujotolud.mypressonline.com/what_are_the_disadvantages_of_solar_thermal_energy.pdfIn PDF document text
    • http://opendouche.xyz/3028386356gq6cc.pdfIn PDF document text
    • https://volinamonapefez.weebly.com/uploads/1/3/4/4/134494747/e5db8388d.pdfIn PDF document text
    • http://vozuzutiwajuzip.getenjoyment.net/popoxulowal.pdfIn PDF document text
    • http://present-mag.ru/dd_3.5_sorcerer_only_spellsc0bpo.pdfIn PDF document text
    • http://mazejofeg.mygamesonline.org/symmetric_and_asymmetric_encryption.pdfIn PDF document text
    • http://futajef.medianewsonline.com/supervisor_job_description.pdfIn PDF document text
    • http://stopro.store/532961961420mc1l.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://laxizibobi.rf.gd/kopig.pdfIn PDF document text
    • https://24b051fc-04af-4e2d-8b9e-4e75c06063ec.filesusr.com/ugd/1a488c_78cd375984264520a48e4caa4255d985.pdf?index=trueIn PDF document text
    • https://0e9c393c-9feb-4465-ae9d-4486bea7a644.filesusr.com/ugd/4b68be_95d333c59c6848da8a31fa92a895bd2a.pdf?index=trueIn PDF document text
    • https://8c805f22-5240-4a8e-9b4d-8499607ff1fc.filesusr.com/ugd/76156b_bbd8e81fc20c4400a426c3e36b36e53e.pdf?index=trueIn PDF document text
    • http://muzulozak.atwebpages.com/52680087303.pdfIn PDF document text
    • http://titesixa.rf.gd/76091193607.pdfIn PDF document text
    • http://zipulosi.atwebpages.com/noxoretejixi.pdfIn PDF document text
    • http://korarazawebev.epizy.com/interpreting_and_analyzing_financial_statements.pdfIn PDF document text
    • http://pevipitoz.atwebpages.com/heart_of_darkness_1991_watch_online.pdfIn PDF document text
    • https://ab0007c4-58ca-4db2-ab23-686bae4d53c1.filesusr.com/ugd/8bf248_8983c50f41ac4f54b6912aa2cc92822f.pdf?index=trueIn PDF document text
    • https://7915398d-c9c2-4241-abdb-40cf742e4b8d.filesusr.com/ugd/d4df0f_24bcb575938e48fea4203a520a2456ea.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_off0000d378.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD378 5692 bytes
SHA-256: 2312e6e7ac601c52d62a57ebc625bd337a51d78c951e06b7ba6ba81842fb545e
font_01_sfnt_off0000e6bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6BD 10724 bytes
SHA-256: a3b251a6db7da05f6762bd501a9e762986f37b026a68b2d7d1a1609059671acb