Malicious PDF — malware analysis report

Static analysis result for SHA-256 50a9f1ff689145cc…

MALICIOUS

PDF

82.4 KB Created: 2021-09-03 15:08:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 90561fd73ea3d8ca1f3df291e79eb3e0 SHA-1: 2b444c5a5995d894d16ad5e69a6b9825768ea1e9 SHA-256: 50a9f1ff689145cc0ba8b3097086f10ba8d8dd33ebe11785957d19565c2c8e16
156 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. The document contains numerous links, many pointing to compromised WordPress sites and disposable hosting, suggesting it functions as a link farm. These links likely lead to phishing pages or further malicious content, aiming to exploit users through deceptive content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160780f4dc6c1f---xizizobusorafedi.pdf
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/9fab58a3b711f7602f9421e05a124347/kupojomubibapigemikolum.pdf
    • https://centrosteadycam.it/wp-content/plugins/super-forms/uploads/php/files/b05cbc8bed38c7e4a76be9ae8d4005f1/71479926354.pdf
    • http://casaalu.com/luutru/files/78531392045.pdf
    • http://xn--spreewaldpension-lbben-9lc.de/meineBilderAlbertGrundschule/file/fiwumuwibiwevinitu.pdf
    • https://taxfirma.com/userfiles/file/sanulapafuseroxaxevivalix.pdf
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/17s68nf9igg8obs43bhua3df2r/47700413869.pdf
    • http://www.deopendeur.org/imgUser/file/fotolojedotex.pdf
    • http://oppedisanorobertosrl.com/userfiles/files/zufanotogatavumewukujo.pdf
    • http://abwlanham.com/uploads/files/14850761947.pdf
    • http://dungcucaytrong.com/images/files/susikepuro.pdf
    • http://ducthanggroup.com/webroot/img/files/30337859842.pdf
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abf75fb0b62---48378645722.pdf
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/elb2tfo82s2lvvlolq5uqj54nj/62394067551.pdf
    • http://restavratorstvo.com/ckfinder/userfiles/files/mewij.pdf
    • https://strings97.hu/userfiles/file/saxufofirivarovabugupu.pdf
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073cc07bd750---milefexutenobezujomox.pdf
    • http://wangyiphk.com/userfiles/71755103657.pdf
    • http://chinalabware.es/d/files/mefopa.pdf
    • https://www.iieng.org/editor/ckfinder/userfiles/files/51823639509.pdf
    • http://kbo.pl/ckfinder/userfiles/files/ledadije.pdf
    • http://studioarchterreni.it/userfiles/files/60355406227.pdf
    • http://alwaysfavorentertainment.com/clients/879371/File/84054838943.pdf
    • https://www.beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/fc0fcf8964d28d11b36504ab7e45262a/zonunuxaximuzujulilapisa.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=reading+compare+and+contrast+worksheets+4th+grade
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df4e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF4E 16792 bytes
font_01_sfnt_off0000f765.bin
6188efb5d8031ce06ff7cd6cdfaaf3bf85cdd0e8fd3d72124b12a99f27d90242
pdf-font-stream PDF embedded font (sfnt) at offset 0xF765 11216 bytes
font_02_sfnt_off00011150.bin
e45615e55502b12cdeccb4e5f1429b2e0914aa951ad89440afa5cf551009c3e0
pdf-font-stream PDF embedded font (sfnt) at offset 0x11150 16312 bytes