Malicious PDF — malware analysis report

Static analysis result for SHA-256 35768ec5c768f95a…

MALICIOUS

PDF

68.7 KB Created: 2021-10-01 20:07:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: cb821e3278ca85b5d8c13067cf7e144b SHA-1: 0595dbe106a8443b4d1dbe037e2fc23cb8fd6c42 SHA-256: 35768ec5c768f95a6c601284843851b60eed67c79731aca50385d68e74c4ce61
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to domains that appear to be compromised or disposable, suggesting a link farm designed to redirect users to malicious sites. The presence of multiple PDF link farm heuristics further supports this conclusion.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://pekingtogo.com/uploads/files/lurozajiberenu.pdf In PDF document text
    • http://www.moyekolodin.com/files/lugalapemomujasam.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16155d290185a1---92810823963.pdfIn PDF document text
    • http://facilitymanagementassociates.com/survey/userfiles/files/80184919200.pdfIn PDF document text
    • https://0800-707-808.com/upload/ckfinder_temp/files/20210909191955.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134e68e5a9be---58632938795.pdfIn PDF document text
    • http://groupementpecheduloir.com/ckfinder/userfiles/files/7684254801.pdfIn PDF document text
    • http://traiteur-ribot.fr/userfiles/file/siminipe.pdfIn PDF document text
    • http://aqbnb.com/uploadfile/file/xotezefofedi.pdfIn PDF document text
    • http://www.moyekolodin.com/files/lajubufapajuvo.pdfIn PDF document text
    • https://gulfsupremesa.com/ckfinder/userfiles/files/bemudotewumosivuzu.pdfIn PDF document text
    • http://www.aunay-sous-auneau.fr/ckfinder/userfiles/files/naxivupipewawi.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/almrfnik4qr686141ct9uei7f2/sejigekilevar.pdfIn PDF document text
    • https://economiadecomunion.net/ckfinder/userfiles/files/puxovonugadetapa.pdfIn PDF document text
    • http://peterpan1996.it/userfiles/files/josanisuwe.pdfIn PDF document text
    • http://studiolorenzoni.eu/userfiles/files/99506302456.pdfIn PDF document text
    • http://china-shengbang.com/upload_fck/file/2021-9-29/20210929185928257708.pdfIn PDF document text
    • http://arniuniversity.in/ci/userfiles/files/45070844917.pdfIn PDF document text
    • http://www.centrosanmarco.eu/img/news/files/30599328432.pdfIn PDF document text
    • http://szilasfood.hu/pic_upload/files/13752474393.pdfIn PDF document text
    • http://tzsunup.com/upload/kumutuwajumikonefore.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=prefix+and+suffix+bingoPDF 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_off0000aeb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAEB9 14952 bytes
SHA-256: 8cf3f76f2defb9a75d6c45ef17fc97013e4ecf6b59c991ca6658e6bf5f3b7fbc
font_01_sfnt_off0000d4c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4C4 10728 bytes
SHA-256: fd7349b37fc54f8c594129913ccd36081ecd87f0fc84bf55c0471cfd5c9fb0bf
font_02_sfnt_off0000ed4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED4A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1