Malicious PDF — malware analysis report

Static analysis result for SHA-256 26e681023382ecd0…

MALICIOUS

PDF

83.2 KB Created: 2021-09-19 00:14:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 5a1cdf584e41e34d5b4ae5bdb0c67885 SHA-1: 4f5c2a984555e644a42fd3cb2ff307b30922eaca SHA-256: 26e681023382ecd061cb0ea40f7958506a5895be22a573b852aaed2bad81bfd0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing 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 phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://daedukgs.com/admin/fckeditor/data/file/20210907135337.pdf In PDF document text
    • https://boyanbolyarski.com/userfiles/file/6815451817.pdfIn PDF document text
    • http://generoussecurity.com/uploads/78170153379.pdfIn PDF document text
    • http://huh.hu/UserFiles/File/48747160512.pdfIn PDF document text
    • http://konberdbio.com/upload/files/widekajubezetosoriputilu.pdfIn PDF document text
    • http://skulpt.in/admin/uploads/file/73874266634.pdfIn PDF document text
    • http://e-menu.hu/editor_up/85794582221.pdfIn PDF document text
    • http://khiensa.com/UserFiles/File/7348637398.pdfIn PDF document text
    • https://gulf-rope.com/images/bulk_images/files/42550679009.pdfIn PDF document text
    • http://cdenito.net/userfiles/file/37600277361.pdfIn PDF document text
    • http://associatedreclaimed.reclaimedoils.com/userfiles/files/numibegirarum.pdfIn PDF document text
    • https://sportyou.fr/ckfinder/userfiles/files/mazozazufenufefaxo.pdfIn PDF document text
    • https://sunwayhk.com/louis/STARKGROUP/ckfinder/userfiles/files/romisuzo.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/16131f5f42f925---pujakuxezolifenukozanix.pdfIn PDF document text
    • http://jfac.kr/ckfinder/userfiles/files/5590382194.pdfIn PDF document text
    • http://montazerangroup.com/uploader/file/xonujiwubowefun.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16146531f59429---masaginupujavadosuji.pdfIn PDF document text
    • http://joltiy.ru/uploads/files/76833843668.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/94649555076.pdfIn PDF document text
    • https://kimansion.com/uploads/file/lakinanupuzolonukagu.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16140e5762d9be---59864603251.pdfIn PDF document text
    • https://spa-salon.ru/ckfinder/userfiles/files/18725250748.pdfIn PDF document text
    • http://teresachild.com/upload/files/24429952530.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/30477632212.pdfIn PDF document text
    • http://isleford.com/filespath/files/20210909030735.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=reset+s4+to+factory+settingsPDF link annotation
    • 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_off0000e274.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE274 16956 bytes
SHA-256: ad5a7c8b679e1d4142a5a025b01c3c254903a2963703758d51dc825767c0004c
font_01_sfnt_off00010e90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E90 10704 bytes
SHA-256: 3f081634dc68d1c305c510e3f9a91811deb034215acf177b92cbdb1217763524
font_02_sfnt_off00012764.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12764 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1