Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b22d524e33d7b99…

MALICIOUS

PDF

70.6 KB Created: 2021-09-29 14:48:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: aff961e40b81f7ee2e3d89c5bd5b4695 SHA-1: 77fd9a8d77481832dbafe5b232479fe086985381 SHA-256: 8b22d524e33d7b99b3d3d6e89d2509df37be391dcb53c7219f9f723a279a0997
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these external links.

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 https://smidgel.ru/uplcv?utm_term=ethanol+chemical+formula+and+structure PDF link annotation
    • http://finadev-groupe.com/userfiles/file/58882480103.pdfIn PDF document text
    • http://chenruichem.com/upload/files/deduwu.pdfIn PDF document text
    • http://boonfagrandhome.com/user_img/files/61215954076.pdfIn PDF document text
    • https://uzunlarpeynir.com/dursun/upload/files/17829689484.pdfIn PDF document text
    • http://meta-min.com/files/riduminijanevig.pdfIn PDF document text
    • http://k1a.ru/images/files/file/gadakisav.pdfIn PDF document text
    • http://trustycctv.com/ckfinder/userfiles/files/tenusajedutekojel.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/d7fab0fb9d4fe0da19f55aecc28962d4/37953819447.pdfIn PDF document text
    • http://montex.pro/uploads/userfiles/file/47515605675.pdfIn PDF document text
    • http://2446665a.ru/ckfinder/userfiles/files/44736345364.pdfIn PDF document text
    • https://hargagila.com/uploads/image/files/96470163610.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d210b68827---witoxurizar.pdfIn PDF document text
    • http://whipitleather.com/userfiles/file/19436221320.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16152a040a1f4d---15250746245.pdfIn PDF document text
    • https://skyzoan.com/cake/beta/userfiles/file/xolima.pdfIn PDF document text
    • http://alda.pl/ckfinder/userfiles/files/21464973227.pdfIn PDF document text
    • http://www-a.euro-ex.net/images/blog/file/22792298010.pdfIn PDF document text
    • http://fazendasaojudastadeu.net/fotosempresa/files/kuverisodaze.pdfIn PDF document text
    • http://studiofapas.it/userfiles/files/manosixejexivet.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/253c647e411a7e5775fd6d16d5cf393d/kazipuwesemav.pdfIn PDF document text
    • http://dulwichtaxi.com/survey/userfiles/files/20008365252.pdfIn PDF document text
    • http://infinijewelry.com/userfiles/file/nevimiwemewakepi.pdfIn PDF document text
    • https://ekransamara.ru/files/luporaw.pdfIn PDF document text
    • http://vevo.keresztessyoptika.hu/elemek/file/wazomutiramubevolerer.pdfIn PDF document text
    • https://telorgabus.com/contents/files/9500367133.pdfIn PDF document text
    • 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_off0000b1e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1E5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c9fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9FC 10824 bytes
SHA-256: 717ff3919aca1c831aceb82498ce784d3eb291d941f9327b4d686226bf1a8c1c
font_02_sfnt_off0000e2b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2B1 16456 bytes
SHA-256: fe9bfc38ccdccdd8f457c98dade719996369b998d1fbf8a22b380b058bf2393f