Malicious PDF — malware analysis report

Static analysis result for SHA-256 88df640af68e0b62…

MALICIOUS

PDF

85.7 KB Created: 2021-09-06 07:25:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 16a2c3ed504283956d2c80f423813849 SHA-1: 3868c4c1b2f547d959703fb4cb918c47e9699d91 SHA-256: 88df640af68e0b62ee8c90d3f3b93e7a3f6ff3f0f20de909f787515c9900a8fa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of links, many of which point to compromised WordPress sites, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://seoulsquare.com/userfiles/file/64070470988.pdf In PDF document text
    • https://vargyasnekonyveles.hu/kepek/other/file/44613820892.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d0d12c15aa---39964056317.pdfIn PDF document text
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/ff623bf2d1ad76eae7f7286833346050/23837081092.pdfIn PDF document text
    • http://msnladyboy.com/ckfinder/userfiles/files/86858354231.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f50a2aa92e---31924037923.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071f2b85c676---37702917534.pdfIn PDF document text
    • http://josepholszowka.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/80553696166.pdfIn PDF document text
    • http://15889163.com/ckupload/files/lisabilub.pdfIn PDF document text
    • https://aihr-iadh.org/uploads/FCK_files/file/68223560910.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/7ccf44887e084f84f77dd0feed6c00ae/5288350426.pdfIn PDF document text
    • http://otohondamientay.com/upload/files/99465813727.pdfIn PDF document text
    • https://history.tlshaa.org.tw/ckfinder/userfiles/files/ralisazexu.pdfIn PDF document text
    • http://gancza.pl/userfiles/file/kafunurasegib.pdfIn PDF document text
    • https://www.auto-ecole-rive-droite.fr/ckfinder/userfiles/files/zelun.pdfIn PDF document text
    • https://feldmann-spedition.de/pics/userfiles/file/savutavitezij.pdfIn PDF document text
    • https://keluargamimpi.com/contents//files/73609207656.pdfIn PDF document text
    • https://somogyplusz.hu/files/wedolejolo.pdfIn PDF document text
    • http://diamantina-joaillerie.com/ckfinder/userfiles/files/togajef.pdfIn PDF document text
    • https://bonafideonline.com.ar/wp-content/plugins/super-forms/uploads/php/files/11db8859bbc7d26e9e05cefbd3c09713/50691352426.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/4r0ldbeq0s2c1gg12enm0ucens/sopizad.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/siriwun.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=wedding+budget+planner+pdfPDF 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_off0000ea0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA0D 10620 bytes
SHA-256: dc56f8447c27e12180ca9cbbee73368b84c55dfa5d1bc07731735ab32692e663
font_01_sfnt_off000101ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011a11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A11 18192 bytes
SHA-256: bf93c5b886881183be834b2f8934823c89f6db6e8eea1105c9347d2ab0df6b92