Malicious PDF — malware analysis report

Static analysis result for SHA-256 f672f4fa0f88d3e1…

MALICIOUS

PDF

88.0 KB Created: 2021-09-08 09:05:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 6d76e66a1edda4985f7da21d3040cded SHA-1: a23f8118789f364ea191c4a5743bf3471c56768b SHA-256: f672f4fa0f88d3e1cc51a0144c003d343a5fcd361423810ead987c320725d52a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics indicate the PDF acts as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The presence of embedded URLs and the nature of the heuristics suggest the PDF is used to redirect users to phishing or malware-hosting sites, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://oniceh.ru/uplcv?utm_term=d%C3%A9veloppeur+web+formation+pdf PDF link annotation
    • http://lezeckastenakosice.sk/upload/files/lefenatezunevezosadagoj.pdfIn PDF document text
    • https://fairtradeportal.pl/userfiles/file/15594117295.pdfIn PDF document text
    • http://debseven.net/UserFiles/File/98467197719.pdfIn PDF document text
    • http://kingsfinancialconsulting.com/userfiles/file/19025021817.pdfIn PDF document text
    • https://cian.hr/userfiles/file/23491807817.pdfIn PDF document text
    • http://osoboebludo.com/ckfinder/userfiles/files/87255250587.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f11140c29a---45185505802.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607132015f06c---zazikubadizasu.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/2963662811.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607654d7304b5---16858462124.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160827afc1baa7---faruxivusoxezanujemetufi.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4a367e858e---votoson.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/53a8444b7ee12b54d81b2997f3b5b527/17757127439.pdfIn PDF document text
    • https://mbzl-pro.xyz/web/img/podborky/files/3327071402.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/d1104e8c737a1800cfe0be1ea73a36f9/sojabefuropinemazagusurop.pdfIn PDF document text
    • http://i-daa-wl.de/userfiles/53895061548.pdfIn PDF document text
    • http://lignumweb.com/site/webroot/uploads/files/nasepajenadujiferifeg.pdfIn PDF document text
    • http://hzbmsj.net/images/upload/File/88909161697.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fbda7757eb---81951259610.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e6e17c6918b---ledutagatujedotekeked.pdfIn PDF document text
    • http://dh-life.com/ckfinder/userfiles/files/70002291869.pdfIn PDF document text
    • http://zoncmswebsitebeheer.nl/files/editor/file/zudejojifigofivoja.pdfIn PDF document text
    • http://caydinhlang.net/userfiles/image/file/kudemarijobekukivusu.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/b283e60cad60a61d6d1af4b051d8d0e5/kobobesagixapebakin.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce14e6e2718---fozami.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/53s4snje41mmn22lru6r3q03h0/ganukale.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_off0000eb17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB17 20420 bytes
SHA-256: 99e2685e45c1e4a28bff94662c6131f707ccaff9b85072dca631ef72f459d599
font_01_sfnt_off00011e90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E90 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000136a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136A7 11040 bytes
SHA-256: 4a7eb1ac378e6b79308b029cf7ab1c0e0b23c977158e13fc801c17533569ddeb