Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ca78789e9dd8474…

MALICIOUS

PDF

67.9 KB Created: 2021-04-04 07:47:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 63adfc9d312ceb0a20770d4d6f8f7197 SHA-1: dcd3e3eb364d997e5a11c51e72e6b2c1b46e5c3e SHA-256: 3ca78789e9dd847457c52b12f8953df9e75bbd708494220cb530f4c0d0521df8
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which are to PDF files hosted on various platforms, suggesting a link farm or SEO poisoning tactic. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://druttle.ru/wix?keyword=reflection+refraction+diffraction+worksheet+middle+school
    • https://cdn-cms.f-static.net/uploads/4456114/normal_60206cfe7113f.pdf
    • https://sifobidegi.weebly.com/uploads/1/3/0/8/130874382/xazorutuloset.pdf
    • https://rinafudafize.weebly.com/uploads/1/3/5/2/135293322/6230537.pdf
    • https://panusefebile.weebly.com/uploads/1/3/5/3/135331690/6581999.pdf
    • https://cdn.sqhk.co/wixefawoz/igihfdB/tekidi.pdf
    • https://cdn.sqhk.co/rovujesox/ZibhcZz/99389909817.pdf
    • http://ratedewu.scienceontheweb.net/28653871290.pdf
    • https://cdn.sqhk.co/guwuweri/a2ibcIZ/xededit.pdf
    • https://cdn.sqhk.co/lusikagidet/sieigcJ/perfect_everything_you_are_to_me.pdf
    • https://cdn.sqhk.co/riragimi/jcheiej/download_game_android_car_simulator_2_mod_apk.pdf
    • https://fisofomopix.weebly.com/uploads/1/3/4/6/134603918/disutofexipome.pdf
    • https://xetutimi.weebly.com/uploads/1/3/0/9/130968997/dfdc29af328.pdf
    • http://gedozudusinap.mygamesonline.org/business_benefits_of_cloud_computing.pdf
    • https://cdn-cms.f-static.net/uploads/4366309/normal_5fe77077548c3.pdf
    • https://cdn.sqhk.co/dexizajifu/yiiGqnx/wixikusajefux.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/takurugilij/50084043821.pdf
    • https://s3.amazonaws.com/rowubunak/scavenger_hunt_template_for_school.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cc0b.bin
2fd678e73a45438ec61e2492540cb53d987bf2269ce2a94565b9c3f2b4340969
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC0B 5424 bytes
font_01_sfnt_off0000de6f.bin
b50775d8db12f361f7b2c1c59f0129d6df361e8c239a0dfdc2bddeefc846dd92
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE6F 9952 bytes