Malicious PDF — malware analysis report

Static analysis result for SHA-256 73d16ec117cf3144…

MALICIOUS

PDF

76.5 KB Created: 2021-05-19 15:49:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 51e92fd6fb3794600624f309ae5b7011 SHA-1: dc19763e0956e47ad3ca4884cc00909a531e2ab3 SHA-256: 73d16ec117cf3144c4d764d832cd1b736638124a541b19a52b377f577e1a1048
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains a large number of external links, many of which appear to be part of an SEO link farm designed to redirect users to malicious sites. The primary redirector URL is https://fokemale.ru/strik?utm_term=how+many+planets+in+hades+star, which is likely used for phishing or to deliver a second-stage payload. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://fokemale.ru/strik?utm_term=how+many+planets+in+hades+star PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4451744/normal_5fdfa5575f411.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454170/normal_60020839514c6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459640/normal_5ff60a2a309b3.pdfIn PDF document text
    • https://leduxuma.weebly.com/uploads/1/3/2/8/132814900/ede2076d57a5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370059/normal_601aad8580b7d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4424036/normal_6006edd9bca7f.pdfIn PDF document text
    • https://fafetomipisiso.weebly.com/uploads/1/3/4/6/134603542/moletajesitixo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407314/normal_5fdbe1c76bc47.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366009/normal_60263af745a38.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374178/normal_6018844de749b.pdfIn PDF document text
    • https://rogapunuki.weebly.com/uploads/1/3/4/3/134375427/xozuwaxegajij_gobezezib_wasibotuxa.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454547/normal_5ff11db7c5547.pdfIn PDF document text
    • https://kovorugoza.weebly.com/uploads/1/3/1/3/131383314/ravugijekaxizozini.pdfIn PDF document text
    • https://wironutoti.weebly.com/uploads/1/3/0/7/130739747/2938820.pdfIn PDF document text
    • https://gekubunog.weebly.com/uploads/1/3/4/2/134235395/c15a054.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4377663/normal_6007566f23d1b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4494657/normal_602ba3d8278db.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390681/normal_6047688e717e2.pdfIn PDF document text
    • https://mogisitubetaw.weebly.com/uploads/1/3/4/4/134496388/6648592.pdfIn PDF document text
    • https://telusexuv.weebly.com/uploads/1/3/0/7/130776200/ruzutixij-zifimetin.pdfIn PDF document text
    • https://pinagoremomaj.weebly.com/uploads/1/3/0/7/130738806/7816888.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000ed28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED28 5356 bytes
SHA-256: c11ab07039e7f7acc9a0dc214cd21c09854e415ce97bf8391bf8f5fe9dea5508
font_01_sfnt_off0000ff3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF3D 11000 bytes
SHA-256: d6c516e81c982088866ca88f9497148e4778f9e3b87cbf759ea57b1581de5898