Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f6615d90f51407e…

MALICIOUS

PDF

75.6 KB Created: 2021-09-13 05:57:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 39aaa52b3aa1fb90135f029f47b43ab3 SHA-1: a163c917fab700029dfdc69902432d372ad55050 SHA-256: 3f6615d90f51407e1c9ef612358424785a1ffae053f66c4b8c243ced38f3808d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. ClamAV and ML classifiers also flagged this PDF as malicious, likely due to its deceptive content and the high density of external links. While no scripts were directly extracted, the nature of the embedded links suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://ketchas.ru/uplcv?utm_term=past+perfect+tense+exercises+worksheet PDF link annotation
    • https://aluminiosarla.com/userfiles_arla/files/90109854104.pdfIn PDF document text
    • https://hotelmitrutarija.com/uploaded/files/zolaturus.pdfIn PDF document text
    • http://arabic.cz/ckfinder/userfiles/files/80467390427.pdfIn PDF document text
    • http://abwessex.com/uploads/files/zasonuvujugudugupe.pdfIn PDF document text
    • https://riolospettacoli.it/filesUploads/file/xarobijizalatajuvu.pdfIn PDF document text
    • https://prawobrzeze.info/userfiles/file/fidugutijaviwiwunibara.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1613839f7741f5---kesomole.pdfIn PDF document text
    • https://hoalavender.net/upload/files/1670661479.pdfIn PDF document text
    • http://hamishehbaharcarpet.com/My_Project/Hamishe_bahar/ahar_img/files/24326042410.pdfIn PDF document text
    • http://prompol.com/media/file/40710056207.pdfIn PDF document text
    • https://zhansq.cn/upload/file/35926796129.pdfIn PDF document text
    • http://cleanking.net/userData/board/file/feradiridaninilesawulupum.pdfIn PDF document text
    • http://www.novosib-sport.ru/ckfinder/userfiles/files/39969185231.pdfIn PDF document text
    • http://architetturaurbanistica.it/userfiles/files/95177658342.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139f5080015d---pifajujun.pdfIn PDF document text
    • http://jyjjapan.jp/files/ckeditor/files/65530882868.pdfIn PDF document text
    • http://lctrading-gmbh.com/ckfinder/userfiles/files/fogaz.pdfIn PDF document text
    • http://uitvaartverzorgingsindex.nl/images/uploads/manuzozidejenanejar.pdfIn PDF document text
    • http://elistaprezentow.pl/userfiles/file/33951554184.pdfIn PDF document text
    • https://bursac.net/userfiles/file/17435891810.pdfIn PDF document text
    • https://dolaodong.com/userfiles/file/94573559436.pdfIn PDF document text
    • http://turbotechnik24.de/userfiles/file/lufirurilogematel.pdfIn PDF document text
    • http://pc-driver.ru/userfiles/files/40444241734.pdfIn PDF document text
    • http://pacemakerpressintl.com/uploads/assets/file/mebemisowuxomibuba.pdfIn PDF document text
    • http://pokwuttibut.com/file_media/file_image/file/tasigorexebebu.pdfIn PDF document text
    • http://shangrilayunnan.com/ckfinder/userfiles/files/xalubipajenipuxelovilov.pdfIn PDF document text
    • https://privatecambodiatour.com/userfiles/file/warote.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_off0000c121.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC121 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d938.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD938 10812 bytes
SHA-256: a0bb3363070f58e0b67fec7a16cea5956e5822071ea596ac85c526940ab3efc8
font_02_sfnt_off0000f23b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF23B 17788 bytes
SHA-256: 00e11ebba4fa37e78e32dd242fd1fb3393c900ed4745746f53bc8a840bc02fb7