Malicious PDF — malware analysis report

Static analysis result for SHA-256 433b488e6b81964b…

MALICIOUS

PDF

86.1 KB Created: 2021-07-14 07:55:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: fd172c3cf7217efde063ce083452b65e SHA-1: 5f28bdd0d4ad9bbc35842bb2e42ce24771404170 SHA-256: 433b488e6b81964bd1e1aeba197ecd90c26750e9d6707e3b2ce2af96ce49c666
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised websites, many of which host other PDF files. This suggests a phishing or malware distribution campaign where the initial PDF serves as a lure to further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://www.awakohchang.com/image/upload/File/2618715190.pdf In PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072d5e49f9d3---39300830721.pdfIn PDF document text
    • http://hanhthien.net/uploads/file/56882538774.pdfIn PDF document text
    • https://menu2uplus.com/images/file/fefiwakulefekapuse.pdfIn PDF document text
    • https://grand-forge.ru/wp-content/plugins/super-forms/uploads/php/files/ed6c254a429a6359e650c02d25302aaf/92656666912.pdfIn PDF document text
    • http://paulbwatkinslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pevumow.pdfIn PDF document text
    • https://www.perfumista.co.uk/wp-content/plugins/super-forms/uploads/php/files/7ba6fdc1944157bc6776981add2f58be/16764555078.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16082c3ef1f6d4---64115983511.pdfIn PDF document text
    • https://hoongnau.com/upload/files/47671046953.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/befa7f5a0c661b25de9a931e66bb951f/pugojazujorusagevadug.pdfIn PDF document text
    • http://bud-drog.pl/userfiles/file/pulirisu.pdfIn PDF document text
    • http://backkwang.com/userData/board/file/puluteralokufapigekorog.pdfIn PDF document text
    • http://duetsepolno.pl/userfiles/file/zilezodovibevukugawe.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/625209189477a212ace2f0d8e48daed0/ponegodelukomadisa.pdfIn PDF document text
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/a452b7ddb6a6bcc6739b6b0992242b62/11030803553.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c2fc7501394---fepuv.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/160ca4f1666f02b85e8aeff29c7cbe96/15819579281.pdfIn PDF document text
    • https://ecole-anglais.com/upload/files/36382305257.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af8701bc517---rutuvufajukapeworupogij.pdfIn PDF document text
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/bf81afdd0e1768731ec08e96691443e1/babopabagog.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/titijofekekidununagipijad.pdfIn PDF document text
    • http://verdantnorwich.com/clients/3/30/306756bb587dffcd11ca74610d845a16/File/weveziraragafoxipogumiko.pdfIn PDF document text
    • http://ersatzmonitor.de/userfiles/file/32861164450.pdfIn PDF document text
    • http://nuovojob.com/userfiles/files/44226325688.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=add+and+subtract+multiply+and+dividePDF 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_off0000ecf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECF8 10956 bytes
SHA-256: 2071e33cff283856fad5abaf2dca41bebfdcdd6608ee7b999a9681580ddedbd8
font_01_sfnt_off00010636.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10636 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E48 17112 bytes
SHA-256: 6b63c7a5ab5692cf8b80aff3edc5bd875ce2daad10b56662cf70306cf4bf5a32