Malicious PDF — malware analysis report

Static analysis result for SHA-256 c35b71e21712a86c…

MALICIOUS

PDF

68.6 KB Created: 2021-09-25 05:23:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 24e894ac52920438d69d3095514e6759 SHA-1: 95b95ae5591bd4ed5a88be94422faa731cb49ac2 SHA-256: c35b71e21712a86cf6ac500290bb5355166b3b91a8c0b34e82b1abe56f5dbdea
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to websites hosted on compromised CMS platforms or are part of a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious sites for further exploitation or phishing. No scripts were extracted, and the document body was unreadable, limiting the analysis of specific user-facing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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.moyekolodin.com/files/bukapinodinepit.pdf In PDF document text
    • http://hosteleriayvending.com/ckfinder/userfiles/files/12813429013.pdfIn PDF document text
    • http://littlepearlspublishing.in/data/eimages/file/59262935370.pdfIn PDF document text
    • http://eventclub.pl/userfiles/file/30132220280.pdfIn PDF document text
    • http://osingenieria.com/images/admin/file/jejoguzirotowejakut.pdfIn PDF document text
    • http://allefrgycg.news-read.com/upload/files/85012322663.pdfIn PDF document text
    • https://mimpiindah88.com/contents/files/xedenon.pdfIn PDF document text
    • https://wanfutemple.urwaydesign.com/data/file/userfiles/files/titegobobamaxufa.pdfIn PDF document text
    • https://dienhoanghean.com/upload/ck/files/10467142708.pdfIn PDF document text
    • http://nhatrangpalacehotel.com/app/webroot/upload/files/gafubamamoputurumi.pdfIn PDF document text
    • https://szallas-karpatalja.hu/upload/basegetuforatokuxabat.pdfIn PDF document text
    • http://talani.nl/userfiles/image/file/detubukewimudepazorojo.pdfIn PDF document text
    • https://lolakarimova.uz/ckfinder/userfiles/files/65800347141.pdfIn PDF document text
    • http://cz-synergy.cz/data/file/rugubijitowa.pdfIn PDF document text
    • http://domgr11.ru/uploads/files/43217927181.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/7v0qtl7gtrn49s9eavrlr5feba/57082709911.pdfIn PDF document text
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/1614d760f53bae---3371627604.pdfIn PDF document text
    • https://delaneyllc.com/ckfinder/userfiles/files/filivoderikagalatez.pdfIn PDF document text
    • https://pointswestliving.com/ckfinder/userfiles/files/buwodifivol.pdfIn PDF document text
    • https://dudikom.pl/userfiles/file/2352449911.pdfIn PDF document text
    • http://stopguepes72.fr/userfiles/file/kafovuwetunodo.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614bc5bfae198---43389911068.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/jokapolafuxijudepat.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=blackjack+21+modPDF 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_off0000aea1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAEA1 10284 bytes
SHA-256: 0df058e32bfc46441eb9f66def506c7a1db0d75888fbd672c9f3a5d2062870a1
font_01_sfnt_off0000c5f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000de08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE08 15484 bytes
SHA-256: 01617274829afe27c3f78d0e6905d446c10a3256690822634f366dfecce0e497