Malicious PDF — malware analysis report

Static analysis result for SHA-256 726cd8733cdc83a0…

MALICIOUS

PDF

69.5 KB Created: 2021-09-27 03:57:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 7ae67bcc25d5b42e8a51b687843afc3d SHA-1: 54e846779ac80782a64a6b04bf3b673da14d9135 SHA-256: 726cd8733cdc83a07b492a001adbdf828bbb2f6a47bd686359d4dc75154fed5b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm, a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and numerous external links suggest it's designed to redirect users to malicious sites, likely for credential harvesting or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://smidgel.ru/uplcv?utm_term=omegle+video+chat+mobile+app PDF link annotation
    • https://fo-prefectures.com/pages/files/77173829358.pdfIn PDF document text
    • https://padservhosting.com/userfiles/file/34447422152.pdfIn PDF document text
    • http://www.dean-cpa.com/files/adminpic/file/dufuboretoxafelenisuv.pdfIn PDF document text
    • http://chatyzvule.cz/uploads/37353113967.pdfIn PDF document text
    • https://aldurra.ly/images-editeur/img/file/97984169858.pdfIn PDF document text
    • http://euroteam.vn/ckfinder/userfiles/files/vekojutodawenaxore.pdfIn PDF document text
    • http://yoron.net/up/files/53920735894.pdfIn PDF document text
    • http://worldwidestationeryholdings.com/files/file/guzivagamuzodejuvu.pdfIn PDF document text
    • http://stellamaris.cz/userfiles/54609404739.pdfIn PDF document text
    • https://khachsan295doson.vn/namthuan/images/news/files/wokimapugozakapon.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/161320cbdb98ec---33960841638.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/gmabsak26r13d4p2np2qm4pkc1/pinutawozusuzirefopila.pdfIn PDF document text
    • http://hilimall.ae/uploads/files/pojolomazogugi.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/gimax.pdfIn PDF document text
    • https://jeevandeepspecialcare.com/ckeditor/ckfinder/userfiles/files/15462044169.pdfIn PDF document text
    • https://vegan-eshop.cz/data/file/77646338131.pdfIn PDF document text
    • http://chinalabware.ru/d/files/60515608306.pdfIn PDF document text
    • http://asesoriazabalburu.org/azaba/files/file/9425738957.pdfIn PDF document text
    • http://spiregene.com/image/files/20210926_162533.pdfIn PDF document text
    • https://thietbixaydungcantho.com/canthomobile2/public/images/sanpham/files/solagabuno.pdfIn PDF document text
    • http://pactolous.hu/upload/file/fuperoxetukisopolikupadap.pdfIn PDF document text
    • http://predit.ru/admin/ckfinder/userfiles/files/72685559236.pdfIn PDF document text
    • http://epilia.com/upload/FCKEditorfile/66492282232.pdfIn PDF document text
    • https://247christianity.org/fckeditor/userfiles/file/290295248431631572343.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_off0000b0cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0CD 15552 bytes
SHA-256: e43bdd56ee70ca40609d19b02fcb69c1da4220ef657002f2a82b79f8c2004e4e
font_01_sfnt_off0000d7d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000efed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFED 10820 bytes
SHA-256: bd1f1da53992c6caa11e27f2397e760b0782a2c9f2b362d51112a41e08cb91aa