Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd09c91664894db8…

MALICIOUS

PDF

79.2 KB Created: 2021-05-31 00:37:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 5378f8b2965a2c79c0c0836d29a58d64 SHA-1: 26a2517bce797604a1175bea9db99836765e824f SHA-256: cd09c91664894db82e8c069fef9f20197426a138dd264dee6abf4714c06b508f
176 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan threat. It contains numerous external links, with a primary URL pointing to a suspicious domain that appears to be part of a link farm. The document body, though heavily obfuscated, suggests a lure related to 'advanced systemcare for android tablet free download', likely to trick users into clicking the embedded malicious links.

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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://golowaki.ru/strik?utm_term=advanced+systemcare+for+android+tablet+free+download PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4451932/normal_60682914916ac.pdfIn PDF document text
    • https://woxopipuwesubaj.weebly.com/uploads/1/3/1/4/131453061/xufofuzuwifilu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370284/normal_60364941b910b.pdfIn PDF document text
    • https://motanufogok.weebly.com/uploads/1/3/1/3/131381166/davevotekes_jegalu_ximitovijubosu.pdfIn PDF document text
    • https://rixevabibevata.weebly.com/uploads/1/3/2/7/132710753/zefoj.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468537/normal_600e5802a2c34.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458124/normal_60100bf8266eb.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4486193/normal_5fcf85480fe9b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476274/normal_6029dc5b1c45e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416495/normal_60039c370932b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380209/normal_606bdd073821e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477138/normal_5fd2af8e080a7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470014/normal_6051b5128c236.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4385648/normal_60b2b5f371c69.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/842951bb-e40b-4e44-a916-efa2a65b4aaf/69653303189.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d5c7dff4-a4c2-4c22-9738-607fcedf0f11/electrical_engineering_technician_courses.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d71a1ef1-1225-420c-a8bd-7694a5479778/basic_mechanical_engineering_projects.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/315c2099-e277-4c3b-bddd-0f1fad65e594/how_much_does_a_1998_coleman_pop_up_camper_weight.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1600f469-d522-4477-9db3-89d39261453c/pemumulevasagive.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/47213588-4a01-43ba-9864-c3654c4b34c2/how_to_ask_for_a_favour_in_email.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3796f33b-e506-41c9-9165-110e231d75ef/33530994046.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a743c2f2-5f58-4b52-be62-38e05bbe895b/sosow.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/05fd00ff-126a-4e95-bea3-0bcba252cfc8/95078316729.pdfIn 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ecdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECDD 5552 bytes
SHA-256: dfb33a2e4673bb0a4043d27ab6c4f9c0e58ed03a2f95f68c3802e59a2cdb30ee
font_01_sfnt_off0000ffb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFB6 1800 bytes
SHA-256: a36eee06fef6ce219692c4ec918276ac99413e4fd1e3666e4031624f9289d620
font_02_sfnt_off00010843.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10843 11456 bytes
SHA-256: c73167672a1553ffc7d09ba2a910302644592e55d729ba3285e793d1570a11f4