Malicious PDF — malware analysis report

Static analysis result for SHA-256 8af336ce123bcb1e…

MALICIOUS

PDF

83.2 KB Created: 2021-10-07 23:54:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: dec3827741fb69efdaf38b7cdcdfecc0 SHA-1: f958bb918c017897ad590b2c177a98bdbf31c300 SHA-256: 8af336ce123bcb1eff233f7f3ed82d6d7c35c7fa1f08013fbc4cb6e4c9b79cc3
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating it likely exploits a vulnerability or contains malicious content. The presence of numerous unique external URIs, many pointing to disposable domains, suggests a link farm designed to obscure the ultimate destination and potentially host malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a strategy to distribute links across many low-reputation domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 5

  • 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 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 http://korea-seals.com/ckfinder/userfiles/files/759562246.pdf In PDF document text
    • http://jagdrevier.hu/upload/images/file/neterozivamajod.pdfIn PDF document text
    • http://volareinmongolfiera.it/userfiles/files/tewis.pdfIn PDF document text
    • https://tutorsbureau.net/userfiles/file/48984140868.pdfIn PDF document text
    • http://ambvet-trefontane.eu/userfiles/files/68855606310.pdfIn PDF document text
    • https://rockyhotelsgroup.com/uploaded/files/33390595984.pdfIn PDF document text
    • http://pietroquatriniarchitetto.eu/userfiles/files/lutanobekivuxebuw.pdfIn PDF document text
    • http://thecuriosityshot.com/69393327733.pdfIn PDF document text
    • https://camping-du-lac-dijon.com/userfiles/fichiers/dejemifowupugu.pdfIn PDF document text
    • http://3suntech.com/UploadFile/file/20211006220131455.pdfIn PDF document text
    • https://bharatiyabhashaparishad.org/ckfinder/userfiles/files/71471743631.pdfIn PDF document text
    • https://casalindasbakery.com/ckfinder/userfiles/files/vegutixegafujafizu.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613532da9eb35---bekedusizejotelonakep.pdfIn PDF document text
    • https://coastalstudio.com/images/main/file/nojunomosamosix.pdfIn PDF document text
    • https://remont-bez-zabot.ru/files/file/religop.pdfIn PDF document text
    • http://vietsonplastic.com/uploads/userfiles/file/limedutizunipuna.pdfIn PDF document text
    • http://5percent-design-action.com/upload/users/files/zaxajekijazopotokimunekos.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/a455c25c5d93fc70b11cc59366a835a3/22795476819.pdfIn PDF document text
    • http://bakefruit.com/uploads/files/202109062132476027.pdfIn PDF document text
    • http://dayou.tw/uploadpic/files/202109271210575826.pdfIn PDF document text
    • http://tongchangkj.com/uploadfile/file///2021091117203642.pdfIn PDF document text
    • http://tcsklife.com/filespath/files/20210926101604.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=cute+names+for+girls+on+snapPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF6F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f786.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF786 10832 bytes
SHA-256: 39ad486797d2c06524529d58bbfe096f250570923279e10614319b49d4710258
font_02_sfnt_off0001108e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1108E 18352 bytes
SHA-256: 725f21f89791cd0f867297601658cc066eebf044149ce9fadfafed30700023d0