Malicious PDF — malware analysis report

Static analysis result for SHA-256 98c1226693b353fe…

MALICIOUS

PDF

98.9 KB Created: 2021-08-08 10:25:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 7b9c509b05118fdeacad983d992f613f SHA-1: 1544d90e92b16fd818a86cdcdd116b2983db71f7 SHA-256: 98c1226693b353fec6cbf17f5a17155a8aa80d889a81098f163e037128dc360d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to these malicious sites, which are presented as a link farm, a common tactic for SEO manipulation or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9892

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://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/3d0dd603ad98182b2567dcb308918eff/takobosobevivavitin.pdf In PDF document text
    • http://serextion2006.com/js/upload/files/31458126629.pdfIn PDF document text
    • http://tomasmrazek.cz/userfiles/file/79290473502.pdfIn PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a3ee7594db---75037255865.pdfIn PDF document text
    • http://zoltysnieg.pl/pliki_wyswig/files/jukowabebunapaze.pdfIn PDF document text
    • https://musikkursus.dk/userfiles/file/42876433233.pdfIn PDF document text
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202105261704049504.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/50137090629.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/f7d68a4688beec6c4c38dc361886f58d/degomewixotupuvozefu.pdfIn PDF document text
    • http://studiosantese.eu/userfiles/files/zevafaladawex.pdfIn PDF document text
    • http://year-c.com/upload_fck/file/2021-7-12/20210712213423940786.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/a16da26a29255b35569bb7e193b5a77e/dalodo.pdfIn PDF document text
    • http://ithaca1966.com/clients/8/85/85e9e0a76fddb83d7689cebc6ab07fae/File/27628739295.pdfIn PDF document text
    • http://www.liveartsaskatchewan.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c6d2811322---73238145274.pdfIn PDF document text
    • http://uci.ir/userfiles/file/87344123479.pdfIn PDF document text
    • http://chanhbon.vn/media/ftp/file/58846337390.pdfIn PDF document text
    • http://fred-robin.com/ckfinder/userfiles/files/saguwuvixaziferomiguwuk.pdfIn PDF document text
    • https://georgiamusicpartners.org/wp-content/plugins/super-forms/uploads/php/files/7e9f2bcbb431ac1b383c2428d5751a6f/44894959212.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160876f3942063---nosile.pdfIn PDF document text
    • http://eschool365.in/js/admin/uploadfiles/file/69511339692.pdfIn PDF document text
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/37g1df813atk1kv2eisaqmso7f/36984247142.pdfIn PDF document text
    • http://serdceprirody.ru/userfiles/file/nidezubaxibiwunipogu.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607a26c4f1cde---fudugazavubudejowi.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/e4bdc05b7311ee8c4fc43e19b8e2336e/vidawulebufapo.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/b984f5df0272e42756e0aa076af0578f/wevowoditamunelotisorabut.pdfIn PDF document text
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/de7a957018ad02efcb17092ee1e7a469/32320700867.pdfIn PDF document text
    • http://bacvietexpress.com/upload/userfiles/files/migezifok.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=descargar+pokemon+mundo+misterioso+equipo+de+rescate+azul+para+ndsPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001048c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1048C 17860 bytes
SHA-256: f56d25fb587c94b1fb4d3467183f787b76dc610455f757401dce332e9d92dc54
font_01_sfnt_off0001325e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1325E 11256 bytes
SHA-256: f9bd2e227c8ff372220fff5b1898904de38fe6730904c24e48b5e2ac76492742
font_02_sfnt_off00014c53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C53 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00016464.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16464 16092 bytes
SHA-256: 9d5144547e0b729630886a3ad3ce48e7da84b0115899dd9c2390406af6f0fecd