Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5031fd14484eaa6…

MALICIOUS

PDF

74.8 KB Created: 2021-09-11 19:26:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 51a98f27b32a1843e8cf66bf3d41427d SHA-1: ff3c857263e9bc13a81da96eab2610627ae9c75d SHA-256: c5031fd14484eaa6c8cc7ba94c50f7a7f5647b04dcc759586f20cacbd7ef0c2f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm for SEO poisoning or phishing. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to malicious sites. The presence of embedded JavaScript suggests it could be used to further obfuscate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://dade666.com/userfiles/202109file/2021091123131570554.pdf In PDF document text
    • http://jrpst.pl/userfiles/file/tulur.pdfIn PDF document text
    • http://turningpointdigital.com/cote_dor_import/admin/ckfinder/userfiles/files/70468881160.pdfIn PDF document text
    • https://gtnet-engine.com/ckfinder/userfiles/files/19668654507.pdfIn PDF document text
    • https://nbtele.com/en/cache/fck_files/file/tazosa.pdfIn PDF document text
    • https://ever-progress.com/upload/files/33437765826.pdfIn PDF document text
    • http://hattingtoemrerogsnedker.dk/userfiles/file/xusujerovimuzelejijuguk.pdfIn PDF document text
    • http://hzaidele.com/images/upload/File/39111624543.pdfIn PDF document text
    • http://dieterheich.de/images/uploads/file/wosumujabejalekuwox.pdfIn PDF document text
    • https://istruttorecinofilo.it/userfiles/file/xopufutitobegu.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/161315bd51e867---dupulimuvexogezixed.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b1b366b56b---75782728205.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/04j3rplsm7ja354pc5ta2dn17j/medejifupela.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b5e969325b---mafavezebiner.pdfIn PDF document text
    • https://aromamarketing.md/img/files/30597533460.pdfIn PDF document text
    • http://lyzjkgm.com/d/files/woxutatetobunadolidirowi.pdfIn PDF document text
    • http://mikomisushiwc.com/uploads/files/zelodosafupukatowosatirev.pdfIn PDF document text
    • http://yh-nutri.com/filespath/files/20210907061941.pdfIn PDF document text
    • http://tipkeo.com/js/ckfinder/userfiles/files/numakuzezelepigaxirowuz.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16134ec5d632a0---11876794417.pdfIn PDF document text
    • https://mk-promotions.com/ckfinder/userfiles/files/gabirerifoduwena.pdfIn PDF document text
    • http://mibenjamin.com/userfiles/file/pagezemozewuxuwe.pdfIn PDF document text
    • http://digitalqwerty.com/ckfinder/userfiles/files/85910923879.pdfIn PDF document text
    • http://friulanapanini.com/images/file/64993741049.pdfIn PDF document text
    • https://digireg.sk/upload/xonebe.pdfIn PDF document text
    • http://kiuanai.com/userfiles/file/gadaxipojigufope.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=solve+the+quadratic+equation+by+completing+squarePDF 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_off0000bee1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBEE1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d6f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F3 16848 bytes
SHA-256: 9b92bc7593c49a793951bc0e69d88a8de0776c58ae68d94a6c180e7a26784c79
font_02_sfnt_off00010213.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10213 11600 bytes
SHA-256: c16d47216c89c9fd3fb3fcafd7a54588896f536805564eec3b8ca0cc3e43e8b6