Malicious PDF — malware analysis report

Static analysis result for SHA-256 7cbc157784381017…

MALICIOUS

PDF

75.7 KB Created: 2021-09-04 06:03:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 8b9e7d9c561937bbde801b402b7d0d24 SHA-1: 016ec988465e607acf8e15988585b5a2e93ad3d9 SHA-256: 7cbc15778438101764d6059f1b598f2b8ec5d46081dea89418d5258ba0830315
164 Risk Score

Malware Insights

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

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, many hosted on compromised CMS upload directories 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 0.9973

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.
  • 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
  • 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://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5e75d62ea6feada86817dd5bca447c7f/45383058600.pdf In PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ab47ca7291---21150266457.pdfIn PDF document text
    • http://aqs-group.it/userfiles/files/2247713867.pdfIn PDF document text
    • https://alariel.be/userfiles/file/goxukizuwudowipodalule.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160a205f88909a---2801829760.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/45c9edd215a450d764608221c75cfaa5/zawogas.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607734473b0b6---85556253081.pdfIn PDF document text
    • http://www.pranabkumar.com/fckimages/file/36856479796.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1cea864e0f---10207473576.pdfIn PDF document text
    • http://copingconversations.com/userfiles/file/4327188099.pdfIn PDF document text
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/867dd61ec42ca73abdc396b2cd15f9d1/fisipagugitavubakipo.pdfIn PDF document text
    • http://casaperferiesantamariagoretti.com/writable/public/userfiles/file/rikinutasusaravinim.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/c3b5ec70e03436f86f29ba345a17e8fd/fidud.pdfIn PDF document text
    • http://abimobiliare.pl/pliki/File/lutelenelanaziviva.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/fexomipolawilazabiz.pdfIn PDF document text
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160737be6117e8---dogexuzelusejofiradi.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609b564f2d468---zusopinerudedowemur.pdfIn PDF document text
    • http://effektfilm.de/files/file/safut.pdfIn PDF document text
    • http://sam-global.ch/files/file/lamovikifopuro.pdfIn PDF document text
    • https://polymadeniyaglar.com/fckeditor/userfiles/file/60113254472.pdfIn PDF document text
    • http://alituncer.com/userfiles/file/kudixusisu.pdfIn PDF document text
    • https://rlmahtani.com/userfiles/files/40301254480.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/29301915553.pdfIn PDF document text
    • https://xn--80aaa1arbfjoe3bzh.xn--p1ai/data/files/22967244226.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=pdf+small+size+reducerPDF 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_off0000c60f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC60F 10476 bytes
SHA-256: 439b4a28b355f667edef8cb8edfc295dee3af6a1204dc4e93b3961543ddf99dd
font_01_sfnt_off0000dde3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDE3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f5f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5F5 16820 bytes
SHA-256: ac71fc2736090f3891946e06542e6f3d795d6f407bdcb28c75ff5338ee67936d