Malicious PDF — malware analysis report

Static analysis result for SHA-256 caee5abf265e4187…

MALICIOUS

PDF

74.1 KB Created: 2021-09-24 23:20:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 32c2aa1ef8f1ba108cab0024fff3e3c2 SHA-1: 8ee41cc646271f4c985e294e9793e9fd8adb8859 SHA-256: caee5abf265e41879a24abbad2ea5861c2d200c2324e356d176165e2db0768d4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, suggesting an attempt to obscure the true destination or distribute payloads. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to leverage search engine optimization for malicious links. No scripts were extracted, but the overall structure and heuristics point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://xn--989ap7r0xbd5x.com/upload/fckeditor/file/papudijebiwovejezuwive.pdf In PDF document text
    • http://beergolfers.com/blog/images/file/benitedaz.pdfIn PDF document text
    • https://lanna-flyingclub.com/ckfinder/userfiles/files/94536492555.pdfIn PDF document text
    • http://www.dr.schure.net/ckfinder/userfiles/files/vidugupiwogujusituj.pdfIn PDF document text
    • http://sushikyototogo.com/uploads/files/bumevubuwejuni.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613e992b91853---nipizifogixuge.pdfIn PDF document text
    • http://areaengineeringsrl.eu/userfiles/files/kuxaso.pdfIn PDF document text
    • https://univerosg.com/ckfinder/userfiles/files/71993269140.pdfIn PDF document text
    • http://huseyindurmuslar.com/images_upload/files/ruxogubunokiri.pdfIn PDF document text
    • http://www.miyadenthai.com/image/upload/File/53043305123.pdfIn PDF document text
    • https://pemaboutiquehotel.com/assets/userfiles/files/bogewe.pdfIn PDF document text
    • https://grupa-energia.pl/attachments/file/12808882971.pdfIn PDF document text
    • https://nabijdefossa.nl/upload/files/xoduwapor.pdfIn PDF document text
    • http://dalnoboy.org/data/filestorage/upload/files/33729003557.pdfIn PDF document text
    • http://marchmontnews.com/imgs/file/dorirawabavasu.pdfIn PDF document text
    • http://le-nora.com/userfiles/file/winedekogedoxelomol.pdfIn PDF document text
    • http://dienlanhlongan.com/upload/files/95644458223.pdfIn PDF document text
    • https://www.playitdirect.ca/ckfinder/uploadfiles/files/tafodizexuk.pdfIn PDF document text
    • http://tagsu.com/attachments/fckattachments/file/13527757323.pdfIn PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/26797099516.pdfIn PDF document text
    • http://rracc.com/file_media/file_image/file/16246503120.pdfIn PDF document text
    • https://its-bulgaria.bg/files/file/wawovirazovonelav.pdfIn PDF document text
    • http://detaycopymatbaa.com/userfiles/file/42947559635.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=hanuman+chalisa+in+pdf+marathiPDF 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_off0000b744.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB744 19992 bytes
SHA-256: 7084c0e7adf5d66e28a4f2e7f0605fdc2b545f3b40743ab35fc97c3c2854d5ca
font_01_sfnt_off0000ea02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA02 10724 bytes
SHA-256: 2d67600e379fe43b9540a9a787e1fd2fcc4912d0de6de6d090e2fc2884e28895
font_02_sfnt_off00010255.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10255 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1