Malicious PDF — malware analysis report

Static analysis result for SHA-256 188255b53fbb8799…

MALICIOUS

PDF

85.6 KB Created: 2021-09-18 06:45:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e1f28b2e871e26cecbfe521bc3d1997c SHA-1: 726f30a5c1899cd4bc39653e0d68bb2b888e2d39 SHA-256: 188255b53fbb8799b5f12966ca3bd76b973fa613807429c3dae2ce9bd7cd3e5a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. While no scripts were directly extracted, the PDF structure and embedded URIs are indicative of a malicious document, potentially leveraging embedded JavaScript for redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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 https://irlanc.ru/uplcv?utm_term=discard+credit+number+generator
    • http://shengnabei.com/uploadfile/file///2021091317051483.pdf
    • http://supermarketdv.ru/files/file/gagemigere.pdf
    • http://yenidenyuzlendirme.com/ckfinder/userfiles/files/danozumopemekas.pdf
    • http://ueros.fr/admin/ckfinder/userfiles/files/gedaxezanutozaped.pdf
    • http://sjanzee.nl/file/20584353521.pdf
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/ojf995ukrn414d0fjr3us3h922/3072151211.pdf
    • http://aalzkj.love-mrt.com/upload/files/noruja.pdf
    • https://chambredhotes-savoie.com/ckfinder/userfiles/files/wofamapukezifavon.pdf
    • https://nitm.ac.in/nitmeghalaya/ckfinder/userfiles/files/20324661404.pdf
    • https://sanipro.ma/app/webroot/uploaderfiles/95542175532.pdf
    • http://drukarnia-skawina.pl/app/webroot/media/files/89212129767.pdf
    • http://www.tiendadelbordado.com/ckfinder/userfiles/files/1161222972.pdf
    • http://elsped.hu/files/file/tinurulipowij.pdf
    • https://topinsolventa.ro/userfiles/file/zuvulamisaxobedosagu.pdf
    • https://equinox-e.com/upload/UserFiles/file/wofoxafigu.pdf
    • http://randygordonlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/45227348052.pdf
    • https://emailing-online.fr/uploads/userfiles/file/77757513373.pdf
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161396ab481e17---winujososebexivuzupatoko.pdf
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131dc5247198---getexojuva.pdf
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613462b02aa04---38134911838.pdf
    • http://pngroup.pl/ckfinder/userfiles/files/suxinajalafagajedoxufe.pdf
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/f0683b15lq2rds2p0hd6bsrl92/kobatomusazelubadopesotof.pdf
    • http://remont-m.com/userfiles/file/90256255532.pdf
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613e4dd04f166---befulobopik.pdf
    • http://www.perchegouet.com/ckfinder/userfiles/files/26960189699.pdf
    • http://opsir.eu/files/file/gizugujugofigi.pdf
    • https://harmony.im/userfiles/file/xamunuwimekenukiguted.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea50.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA50 16792 bytes
font_01_sfnt_off00010262.bin
64e092d285315e4451020cf8d7d80491f4312c0aeee5dc74ff441b077901cb36
pdf-font-stream PDF embedded font (sfnt) at offset 0x10262 17276 bytes
font_02_sfnt_off00012ede.bin
330a4879a74ae64c506802a9b7d41f0268e975e876c41d53d6ffdf0c533125d8
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EDE 10908 bytes