Malicious PDF — malware analysis report

Static analysis result for SHA-256 198a52de817c7318…

MALICIOUS

PDF

81.5 KB Created: 2021-09-04 03:01:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 186ef93e1c20bd07bdeb10a6dca724b3 SHA-1: 98a11c3527d02a8a3931682d9c8c1356b7766a60 SHA-256: 198a52de817c73182ac40617ca1db4a14f60deed7667f6d95a124274aa1a9626
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 potentially compromised WordPress sites or disposable hosting domains, indicating a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • 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://hengtaixin.com/HangShun/ckfinder/userfiles/files/vawexopevo.pdf In PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a105387c921---mupizezezaxefuse.pdfIn PDF document text
    • http://turexpert.md/userfiles/images/file/4952357020.pdfIn PDF document text
    • https://www.indoorclub-informa.com/boletines/img/file/61249955676.pdfIn PDF document text
    • http://artospace.com/pics/file/71859581815.pdfIn PDF document text
    • https://eyetracking.pl/userfiles/file/40909267831.pdfIn PDF document text
    • https://infiniteprospects.com/FCKeditor/file/28444937538.pdfIn PDF document text
    • http://china-miyaco.com/img/file/2021528155118.pdfIn PDF document text
    • https://lifecareproduct.in/ckfinder/userfiles/files/72589179389.pdfIn PDF document text
    • http://boek.se/bilder_umeny/File/puzawutepo.pdfIn PDF document text
    • https://clubslotalmatriche.com/calcas/file/59106820722.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/e0f0d54a0d348b075c917242ae191235/pedupi.pdfIn PDF document text
    • https://juhaszautovill.hu/userfiles/file/jetupixizipav.pdfIn PDF document text
    • http://whuntex.info/userfiles/file/76055922502.pdfIn PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/781e2695db93b2b7e37ef39a6d2c3cf5/zomefaxudikoxezozenenuxed.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160772bccc3f03---zebibagemomimuze.pdfIn PDF document text
    • http://forter.vn/hinhanh/file/tuxikolexigipapolesogi.pdfIn PDF document text
    • http://inlovehuahin.com/file_media/file_image/file/zuxixavapadizerotofotivan.pdfIn PDF document text
    • http://dolphinegypt.net/userfiles/file/17476040454.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/32346121756.pdfIn PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/c3b1h3pm4g47dop6h32cf6o0k5/16986297667.pdfIn PDF document text
    • http://iltorg.ru/upload/file/xirirosofa.pdfIn PDF document text
    • https://gbagencement.fr/uploads/file/bevilate.pdfIn PDF document text
    • http://www.dismaplant.com/ckfinder/userfiles/files/34565487336.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=historia+del+antiguo+egipto+pdf+ian+shawPDF 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_off0000d857.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD857 10952 bytes
SHA-256: 7efaa8581a0e50ad068e2596d0a91d4d97f002ec6a962327f871107053bec2d8
font_01_sfnt_off0000f17b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF17B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001098d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1098D 18208 bytes
SHA-256: 7783be7fc2a73619700597818fb424530715ea2046bbb73e691bdfb1db65b1a3