Malicious PDF — malware analysis report

Static analysis result for SHA-256 a471594c67f7765e…

MALICIOUS

PDF

88.9 KB Created: 2021-10-07 09:27:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: fb6460d16cb804b82d170e5e3298fb7c SHA-1: da19b797c7150d1d9ee37f9f9530332193b353a0 SHA-256: a471594c67f7765e6e0d7ca583acf7a4bc533f9e199e2e9b71b7c16ae0efaa37
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these redirects.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://crysiq.ru/uplcv?utm_term=ca+inter+corporate+and+other+laws+notes PDF link annotation
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614e1a97a3391---zilaboligab.pdfIn PDF document text
    • http://cppzone.ru/users/blogs/file/veburuserowupaxapumimapo.pdfIn PDF document text
    • https://ppntassone.it/dati/upload/file/jikijimodozeri.pdfIn PDF document text
    • http://ck-buhgalter.ru/userfiles/file/suxolivizisusovozu.pdfIn PDF document text
    • http://geoass.eu/userfiles/files/tuwis.pdfIn PDF document text
    • http://kondicionery-domodedovo.ru/upload_picture/file/fugusofojukezarir.pdfIn PDF document text
    • https://zerling.eu/nico/images/files/limiveromiposimigutut.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/161492791885fb---96720499927.pdfIn PDF document text
    • http://savoie-outils-coupants.com/ckfinder/userfiles/files/matukerupo.pdfIn PDF document text
    • https://voziky-paletove.cz/mctree.cz/pictures/other/files/30209326553.pdfIn PDF document text
    • http://conservativista.com/js/ckfinder/userfiles/files/dafese.pdfIn PDF document text
    • https://eguiders.com/uploads/5613891721.pdfIn PDF document text
    • http://appartementslisa.it/an3_Uploads/file/6616185762.pdfIn PDF document text
    • http://ty-int.com/files/files/povul.pdfIn PDF document text
    • https://minhgianggroup.vn/upload/files/94336562267.pdfIn PDF document text
    • http://icoenergia.com/userfiles/files/wekenoxemawi.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/98ec07c38b1272ba93b3c3ab34b0fcd8/4125595962.pdfIn PDF document text
    • http://coutleelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zefixajejuwosod.pdfIn PDF document text
    • http://zulassungsdienst4you.de/bilder/file/67291268216.pdfIn PDF document text
    • https://akanaymatbaa.com/calisma2/files/uploads/99433765977.pdfIn PDF document text
    • https://amgaa.org/temp/files/biguxawu.pdfIn PDF document text
    • http://madinaboys.com/easydo%20v2.00/files/uploads/rebidopizesefu.pdfIn PDF document text
    • http://constantcontinuity.com/membership/data/files/14132642059.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_off0000f0a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000108b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108B8 20080 bytes
SHA-256: bc0b501a57ee46543586221f4677d491d9acb74ff502cc05e13b61100c7e55c0
font_02_sfnt_off00013ca7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CA7 10728 bytes
SHA-256: ad7f9e5b885e7e34aee9d48a4823cfa2062899cdb2c3a3405bb4d99d7459e980