Malicious PDF — malware analysis report

Static analysis result for SHA-256 c28ef5b16d279655…

MALICIOUS

PDF

69.1 KB Created: 2021-09-26 04:43:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: aefc7051a779c7c801307c8eafd53013 SHA-1: 097aeb44aff43e06101babc724cbd466dee2bdb4 SHA-256: c28ef5b16d279655fbb1b1e9554a08bd02f1dc26455a16f6a1568f80850ec102
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution through these links. The presence of 'utm_term' parameters in some URLs further supports a campaign-like structure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://archism.ru/uplcv?utm_term=play+bloons+td+5 PDF link annotation
    • https://turkuazhost.com/calisma2/files/uploads/vanirusuwolajipu.pdfIn PDF document text
    • https://renetravel.ro/images/files/waxulenofavunog.pdfIn PDF document text
    • http://azbuka-d.ru/ckfinder/userfiles/files/69069859921.pdfIn PDF document text
    • https://securitydm.rs/slicice/file/bizomumawivawerofiji.pdfIn PDF document text
    • https://shriayurvednagpur.org/public/ckfinder/userfiles/files/95341818825.pdfIn PDF document text
    • https://factorysales.com/userfiles/files/30108971680.pdfIn PDF document text
    • http://shriramashramps.org/userfiles/file/88881958227.pdfIn PDF document text
    • http://lrpharmaceutical.com/upload/files/rigoxutazonug.pdfIn PDF document text
    • http://oroblupiscine.it/userfiles/files/dazejesuv.pdfIn PDF document text
    • http://propack-th.com/image/upload/File/nekixapetupufolofetovuxib.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/74210676103.pdfIn PDF document text
    • https://negaratoto.com/contents/files/jazebadataxizelizasowukag.pdfIn PDF document text
    • http://nuovartea.eu/userfiles/files/vuzilibudofejazalar.pdfIn PDF document text
    • http://liveisagenix.com/ckfinder/userfiles/files/ponapupagaluneferigefela.pdfIn PDF document text
    • http://sinching.com/uploadpic/files/202109021308579782.pdfIn PDF document text
    • http://canissapiens.com/images/uploads/file/36482321552.pdfIn PDF document text
    • https://trongtrucsolution.com/uploads/files/24348643300.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/b8c65f85d6c7bd148e4ba6d6bc25017a/90202646301.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/16148b20f1cd37---76707521241.pdfIn PDF document text
    • https://webhosting4.net/media/file/29996236914.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/876c9a9a1f5911bbde156154638f88e7/mobijenaminuxuduwuwoluvip.pdfIn PDF document text
    • http://tcsklife.com/filespath/files/20210910120259.pdfIn PDF document text
    • https://adurucui.com/ckfinder/files/zesisipudami.pdfIn PDF document text
    • http://elard-group.com/ckfinder/userfiles/files/zijixofumewirup.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_off0000b094.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB094 10304 bytes
SHA-256: 69ee0df7a1c0e0e01a94a08de7cfa77cb3bfcaa8b3d19586c4fc91337bb39631
font_01_sfnt_off0000c808.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC808 15468 bytes
SHA-256: 1329d6fe0ccbadc6af578be4ced4d6de50ec4ffa6f52189275fa2a7624d351e3
font_02_sfnt_off0000ef63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF63 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1