Malicious PDF — malware analysis report

Static analysis result for SHA-256 13bb50f4da825e5d…

MALICIOUS

PDF

71.1 KB Created: 2020-12-01 15:43:29 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 630b8ba4d7775b2727a6752a61f53e5b SHA-1: 2bb47d4dceb48fb72ce0b7c98d2cee159eaafad7 SHA-256: 13bb50f4da825e5d58b0a2c3e56cad37a8beaa971190502843a065e21ee37b2f
252 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, routes users through malicious redirector infrastructure and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://traffmen.ru/strik?utm_term=advanced+comma+worksheets In PDF document text
    • https://static.s123-cdn-static.com/uploads/4482623/normal_5fc464b45aed1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456134/normal_5fa4166a60439.pdfIn PDF document text
    • https://mupibidegupek.weebly.com/uploads/1/3/0/8/130874042/cd401ac122e60.pdfIn PDF document text
    • https://vasabofilusav.weebly.com/uploads/1/3/4/5/134585229/7045709.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422163/normal_5f9c47fb613e2.pdfIn PDF document text
    • https://xekitagib.weebly.com/uploads/1/3/4/6/134668592/fesiziriwak.pdfIn PDF document text
    • https://ditiwudo.weebly.com/uploads/1/3/1/4/131452947/81593d86d4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385217/normal_5f9bcdf0ba24a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4492575/normal_5fc5559b45e38.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378857/normal_5f8a4f25a18dc.pdfIn PDF document text
    • https://vamekatowozi.weebly.com/uploads/1/3/0/8/130814347/8689.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390071/normal_5f8fa8e099759.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://static1.squarespace.com/static/5fbce344be7cfc36344e8aaf/t/5fbd01383fdc31513a10553e/1606222137237/new_mastermind_game_rules.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f27b902e-9cb3-4eb5-8377-d02a50dc9ca4/megaman_zero_2_boss_theme.pdfIn PDF document text
    • https://static1.squarespace.com/static/5fbce344be7cfc36344e8aaf/t/5fbe0e82f8cdb769c6aaa73d/1606291074835/17489475182.pdfIn PDF document text
    • https://static1.squarespace.com/static/5fbce344be7cfc36344e8aaf/t/5fbe09b9e18c5c478ec2d6fb/1606289851001/wubisatozegupesim.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_off0000cab1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAB1 5092 bytes
SHA-256: 51382a60777b26fab238c07c9a0659e8a230933f53e3a16069926acf438055e7
font_01_sfnt_off0000dbd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBD9 10396 bytes
SHA-256: 5eb14bf8e175263fa92ee65ef780f0bfd0390075b7185c649d417a0b0fc2b7f3
font_02_sfnt_off0000ff47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF47 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f