Malicious PDF — malware analysis report

Static analysis result for SHA-256 987c7a32e1e34f2d…

MALICIOUS

PDF

73.0 KB Created: 2021-09-25 12:57:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 90747a17c428046f1d32fdf7762aa1ac SHA-1: d34c417c98ca158855f6cc60cd9d0c6847fb0b44 SHA-256: 987c7a32e1e34f2dd1985666004307dcc3cdaaea878451279e414e9301036fc0
126 Risk Score

Malware Insights

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

The file was detected as a malicious PDF by multiple heuristics and a machine learning classifier. It contains numerous external URIs and is identified as a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. The ML classifier output of 0.991481 and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

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 https://cructi.ru/uplcv?utm_term=granny+picture+frame+horror+game PDF link annotation
    • http://natpuedu.in/userfiles/file/97148764828.pdfIn PDF document text
    • http://paolacaone.eu/userfiles/files/bikenaloza.pdfIn PDF document text
    • http://bsp-plovdiv.org/ckfinder/userfiles/files/miburozajuwabijutazaba.pdfIn PDF document text
    • http://lisaarkin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/74987917859.pdfIn PDF document text
    • http://www.gamylai.vn/uploads/files/18437077365.pdfIn PDF document text
    • http://omnoiptv.com/outscapes/admin/ckeditor/uploads/ck/files/92180561798.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/50847932419.pdfIn PDF document text
    • http://orderleesushi.com/uploads/files/fixizovotiroguge.pdfIn PDF document text
    • http://letresorellebio.it/userfiles/files/zoriwogijebok.pdfIn PDF document text
    • http://avsa.org/sites/default/files/images/files/9657442739.pdfIn PDF document text
    • http://tk-weld.com/images/library/File/11691134588.pdfIn PDF document text
    • https://ruiguoex.com/upfile/files/2021/09/05/34566336610.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161326ec8bfea1---32472822929.pdfIn PDF document text
    • https://dgssu.com/upfolder/e/files/20210909060258.pdfIn PDF document text
    • https://residenciasanamaro.es/userfiles/files/1977137537.pdfIn PDF document text
    • http://monkey-do.net/userfiles/file/vokedulonef.pdfIn PDF document text
    • http://bakefruit.com/uploads/files/202109230108198343.pdfIn PDF document text
    • http://strahyi.ru/images/file/6189183593.pdfIn PDF document text
    • https://cqhuaan.myhost360.cn/upload/files/09-20-17-01-48-19.pdfIn PDF document text
    • http://ventmetal.ru/userfiles/files/gifiwinuzidisi.pdfIn PDF document text
    • https://adamslakeband.org/userfiles/file/41712285228.pdfIn PDF document text
    • https://strategie-forex.com/ckfinder/userfiles/files/9453396300.pdfIn PDF document text
    • https://expobar.vn/app/webroot/files/images/pages/files/14659927150.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/bff18eaf941124622f4018aee4757ad7/kixexinomufajijabowofibe.pdfIn PDF document text
    • http://westernmaki.com/uploads/files/nekovupoxe.pdfIn PDF document text
    • http://konsultacjenaukowe.eu/Upload/file/68315252661.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_off0000b61d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB61D 10968 bytes
SHA-256: 6295bf6b94ebaf3fd452b160273a454c95f08a32992f11796e73371cabee12f2
font_01_sfnt_off0000cf6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF6F 17412 bytes
SHA-256: 33d6e2d9df157318a5248717c548f844aaa033f1ae0cad3d650ff633acea75d7
font_02_sfnt_off0000fbe5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBE5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1