Malicious PDF — malware analysis report

Static analysis result for SHA-256 3adb27cb89683c94…

MALICIOUS

PDF

87.7 KB Created: 2021-07-17 03:58:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: b85a7115aaab94a8afacfd7e9e7af313 SHA-1: 96cb439e79f02fb59d1e0b1a4e567f1b948a111f SHA-256: 3adb27cb89683c9442bcca7c5970cecde74a3ce5aa67f64f2b6ffe5a4a0a6ba8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond what the heuristics indicate.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16075ed2d060a2---65111136498.pdf In PDF document text
    • http://granite1962.com/clients/869125/File/64657258750.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/86105860789.pdfIn PDF document text
    • https://call-life.com/ckfinder/userfiles/files/tisedonajop.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/suvunidem.pdfIn PDF document text
    • http://fritz-fahrlaender.ch/download/14849593877.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/160975dc4a9cdf---sugux.pdfIn PDF document text
    • https://satuldelut.ro/ckfinder/userfiles/files/sabugonami.pdfIn PDF document text
    • https://master-service.ro/images/file/dowaludisipiz.pdfIn PDF document text
    • http://trendstyleimage.com/uploads/ckfinder/userfiles/files/jetavabikonibojagu.pdfIn PDF document text
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160788d02a9bbe---45435035866.pdfIn PDF document text
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/26c71b02daa4896a9767ec0f56fc1230/47597404136.pdfIn PDF document text
    • http://111-orte.de/testarea/cwsCMSlight/media/files/zenewenamowo.pdfIn PDF document text
    • https://thinkglobalcompliance.com/ckfinder/userfiles/files/matafusaxetam.pdfIn PDF document text
    • https://tortugafilms.ca/adminfiles/file/kisuka.pdfIn PDF document text
    • http://abc-tel.ru/data/File/65706942985.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/jc8rbflq8l81ffcfrs9dc8l6f7/wodinagamadonid.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c3035337b5---ruxuniref.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac329d4a83---jokuzukibojematok.pdfIn PDF document text
    • http://caycanhtuyhien.com/uploads/image/files/misuxuw.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/1607fcf6779162---mepuzupodis.pdfIn PDF document text
    • http://mateuszkucharski.pl/admin/file/6685159594.pdfIn PDF document text
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bef59038c8---sewizetebokubazapek.pdfIn PDF document text
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/bih2eidsi7j8kfi9q1atun3ha3/85127978998.pdfIn PDF document text
    • http://xinyaoqiye.com/upload_fck/file/2021-6-1/20210601215612557242.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dc3a540a3c5---52113981261.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=elements+of+thoughtPDF 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_off0000f562.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF562 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010d74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D74 17196 bytes
SHA-256: f95cb6b8b6aa65167c8f8b7ceb35b15355ec5a930c9d07a12ea902cc46d5bda7
font_02_sfnt_off00013a6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A6F 10392 bytes
SHA-256: 3918f55ecf392fe579081fbc146a588467c93496c299c4cb2f5488de6b710078