Malicious PDF — malware analysis report

Static analysis result for SHA-256 d87defe0648896da…

MALICIOUS

PDF

85.6 KB Created: 2021-09-21 19:54:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 97a2cb1465da6ab0658d0b4993ce876d SHA-1: 8900ad28147fd14ce8bebe58c992c2d803556c8f SHA-256: d87defe0648896da51d36959d963ea7490e6b87cf28b7fb7688f7a6ce82a4d88
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to obscure the final destination. The presence of these links suggests an attempt to lure users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://chcial.ru/uplcv?utm_term=giantess+games+on+android PDF link annotation
    • https://cdmsig1.com/ckfinder/userfiles/files/5754385310.pdfIn PDF document text
    • http://vektor-bezpeki.com/userfiles/files/kodinusumamobuzemiwolez.pdfIn PDF document text
    • http://travelcenterpuntos.com/campannas/file/defixiwufetalorulujak.pdfIn PDF document text
    • https://speculatio.in/ci/userfiles/files/16087175502.pdfIn PDF document text
    • http://fivelscope.net/fckimages/76180415469.pdfIn PDF document text
    • http://wu-pao.com/upfiles/editor/files/jofalag.pdfIn PDF document text
    • http://96stone.ru/userfiles/file/1679475032.pdfIn PDF document text
    • http://lifecare4all.com/upload/files/40428715941.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/c9a69f0c8480f9173114f48ebf3f358a/78910853941.pdfIn PDF document text
    • http://kovove-ploty-brany-zabradli.cz/UserFiles/File/30297505007.pdfIn PDF document text
    • http://favourtec.com/attachment/file/78925702745.pdfIn PDF document text
    • http://mayinmaunhat.com/upload/files/91794418695.pdfIn PDF document text
    • https://es21sys.com/userfiles/file/51398190531.pdfIn PDF document text
    • http://pro-elec.ru/ckfinder/userfiles/files/71824193210.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614618b7e066d---tafov.pdfIn PDF document text
    • http://fabrikando.com/cmsimple/images/file/77894475978.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139ac8469fa3---noxujebudupukitatukase.pdfIn PDF document text
    • https://autoandtruckrepair.net/nbloom/fckuploads/file/vojumanoxiwamupafiwitubu.pdfIn PDF document text
    • https://hinodecoder.com/userfiles/file/lariwitifaviboloror.pdfIn PDF document text
    • http://www.slenderclub.cz/ckfinder/userfiles/files/nivejoretudoniruw.pdfIn PDF document text
    • https://karpataljaturizmus.hu/upload/72398758047.pdfIn PDF document text
    • https://slezanie.eu/userfiles/file/xesimomur.pdfIn PDF document text
    • http://haki.vn/uploads/files/91525849707.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_off0000ee3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE3A 16740 bytes
SHA-256: 3f49dc89dce1ea51cf08ce2a822642bc7b99f0138181cbfac6887d04d1a4b3b1
font_01_sfnt_off00011973.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11973 10584 bytes
SHA-256: c8f7a03eb7584f24cfee26262357ecf7b1ab774625e672d143840e38e71dc3a5
font_02_sfnt_off0001316e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1316E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1