Malicious PDF — malware analysis report

Static analysis result for SHA-256 b996ca08287708c2…

MALICIOUS

PDF

71.2 KB Created: 2021-09-02 13:21:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5a092c74b1f14b8958b5dc0727204fcf SHA-1: e5d26bbfcbac313a431858fa4110254a0154eabf SHA-256: b996ca08287708c2203563378fab8e4b71b59d02ac328f37919ce8763f16656f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external links, many pointing to compromised or disposable hosting. This suggests the document is designed to act as a link farm, likely to redirect users to phishing sites or download further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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 http://irinaburmistrova.ru/files/76001525505.pdf In PDF document text
    • http://casaalu.com/luutru/files/32531199097.pdfIn PDF document text
    • http://hoanggiaphatland.com/uploads/image/files/gupadodazukilekikap.pdfIn PDF document text
    • http://eg-connect.com/php_codes/Scott/VieauAssociates/code/userfiles/file/16151872117.pdfIn PDF document text
    • https://thepainter.asia/upload/files/muwolibo.pdfIn PDF document text
    • http://ownlines.com/upfiles/file/mofiwodabubizimowixoji.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/4c9380ff95f6e3e01b80038446715f84/15928122452.pdfIn PDF document text
    • http://cps-mbstu.edu.bd/app/webroot/js/ckfinder/userfiles/files/43787992467.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f91b837361f---70419230575.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/c6io5miie5hinjlv5ekd3c38g4/31609394237.pdfIn PDF document text
    • http://fusheng-vietnam.vn/admin/webroot/upload/image/files/silejoromezami.pdfIn PDF document text
    • https://signaturetowerpune.com/wp-content/plugins/super-forms/uploads/php/files/btpqjqkhkpjog8en3u0rnvoup4/rizenanipofadoreve.pdfIn PDF document text
    • http://chothuexeninhbinh.net/data/dulieu/files/zosololesonikirot.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607a5e046540e---35149411197.pdfIn PDF document text
    • http://annamsaigonlaw.com/upload/files/bugukilaper.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c31ee139611---96582474331.pdfIn PDF document text
    • http://amidoux-peintures.com/ckfinder/userfiles/files/87170160846.pdfIn PDF document text
    • http://svatba-emi.com/uploads/pages/files/3594523091.pdfIn PDF document text
    • https://deniz-sogutma.org/img/userfiles/file/97207208179.pdfIn PDF document text
    • http://www.waetsukai.jp/system/ckfinder/userfiles/files/vosaxaxoxepava.pdfIn PDF document text
    • http://wshs67rocks.com/clients/9/94/942520bde836a0b401740df6f3d23d35/File/zudavupomatijusowugogarof.pdfIn PDF document text
    • http://quinta.cl/upload/files/49223189412.pdfIn PDF document text
    • http://jshtextile.com/UserFiles/file///33663314371.pdfIn PDF document text
    • https://jamuiboe.com/webroot/upload_media/ludonopis.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/160731b9f4601b---47252690580.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=fundamentals+of+advanced+accounting+6th+edition+pdf+free+downloadPDF 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_off0000b443.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB443 11464 bytes
SHA-256: 094c54bcc49d75ae5d1a48d381b6457cd1a1aee32424eb34f591cd2ca02bf3b2
font_01_sfnt_off0000cf08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF08 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e71a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE71A 15680 bytes
SHA-256: 74f35c6f6e3a6a4c5d0dd36c53fda254ab57b363fdabab744ce5d0de627e7697