Malicious PDF — malware analysis report

Static analysis result for SHA-256 717887e136c57065…

MALICIOUS

PDF

69.7 KB Created: 2021-09-09 02:28:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 71bc33a054ce982fb4065b6d0ef74ed3 SHA-1: d651d66bed883e8b44d45685fa119cbdc73d56b6 SHA-256: 717887e136c57065b98dff41ba7acbe17f86d3b6d10200c22b0178ebec7ce071
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to multiple external URLs, some hosted on compromised WordPress sites, suggesting an attempt to distribute further malware or conduct phishing. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://10s317.com/uploads/files/202109050928464600.pdf In PDF document text
    • https://matratva.in/userfiles/file/vujutezuzuzenolibasobolo.pdfIn PDF document text
    • http://vektor-bezpeki.com/userfiles/files/53478690285.pdfIn PDF document text
    • http://cps-mbstu.edu.bd/app/webroot/js/ckfinder/userfiles/files/bogikow.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/deb2774e6ded66018e2a0e21fb5f220d/39850813510.pdfIn PDF document text
    • https://octvads.site/js/ckfinder/userfiles/files/49781060182.pdfIn PDF document text
    • http://laiyi-art.com/userfiles/file/zopige.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613408dcc5808---zinebatuzuda.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161353aeaac9b9---zigofezi.pdfIn PDF document text
    • https://kanalprofi.at/UserFiles/file/51475233058.pdfIn PDF document text
    • http://cottoneauto.it/userfiles/files/60580178481.pdfIn PDF document text
    • https://ceccarmehedinti.ro/userfiles/file/wipaxexipotunekobukuwabol.pdfIn PDF document text
    • http://malagi.pl/user-files/fck/file/ruboxok.pdfIn PDF document text
    • http://secretinvitation.net/images/files/jerafameferituramomaka.pdfIn PDF document text
    • http://momsystem.ru/public/file/62492449328.pdfIn PDF document text
    • https://olterus.org/contents/files/sabilapef.pdfIn PDF document text
    • http://oaklandscreche.ie/userfiles/files/34394865106.pdfIn PDF document text
    • http://nollve.com/img/editor/image/file/luluxigapixupejubiwelik.pdfIn PDF document text
    • https://grupo-kayros.com/userfiles/file/77175448529.pdfIn PDF document text
    • https://cet.sk/res/file/43162336112.pdfIn PDF document text
    • http://paolacaone.eu/userfiles/files/bikenaloza.pdfIn PDF document text
    • http://jatechkj.pl/upload/fck/file/monemelubamekawime.pdfIn PDF document text
    • https://yensaovinastar.com/media/files/41510750597.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=rhythm+heaven+for+androidPDF 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_off0000af82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF82 16120 bytes
SHA-256: 6f52ab403311f9d80ccaac056525078351978bd1a8817d4a456fdddf8e96d767
font_01_sfnt_off0000d8f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8F1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f108.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF108 10632 bytes
SHA-256: 9777b8f070635caac9a8f8bcd3fea8e83531d8f0f22cbc70b15f5b6958af0d89