Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3549f64b473b396…

MALICIOUS

PDF

82.8 KB Created: 2021-08-24 19:31:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0e3f301b5a50346a89988df6e462094a SHA-1: 43775613417af426cc430048778df32cb59aa776 SHA-256: f3549f64b473b396c19332529a4a3a7abf749ce0445ae1201e43d8d3f09d50b4
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to obscure the final malicious destination. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple compromised CMS upload links and disposable hosting reinforces the malicious nature of the PDF's content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • 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.
  • 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://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bee07958fc2---80868506772.pdf In PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9a08a3954---85362326764.pdfIn PDF document text
    • http://ktcz.eu/files/files/47307878421.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fdddf6733d7---86975546242.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/160b4539f80173---43741881277.pdfIn PDF document text
    • http://brmhn.com/userfiles/file/20210520113552_t3wxv7.pdfIn PDF document text
    • https://coluer.ir/documents/file/lugef.pdfIn PDF document text
    • http://goodfortune.hk/UpLoadFile/file///2791142956.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/b39cff76d7e59d5275112eb9a67e9afe/mifusorurobok.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/292a10473e4163c6ccf5c85709246a81/tateporateboberudiwelere.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f90a807e36c---27670945981.pdfIn PDF document text
    • http://facilitymanagementassociates.com/survey/userfiles/files/70320486287.pdfIn PDF document text
    • https://muguet.fr/sites/default/files/file/89756264247.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ad68534f9f6---56519225731.pdfIn PDF document text
    • http://dietaltop.com/userfiles/files/xotowugit.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/161192d81ea145---71456168852.pdfIn PDF document text
    • https://www.mds-horizons.com/upload/files/11011804394.pdfIn PDF document text
    • https://jclifeschools.org/wp-content/plugins/super-forms/uploads/php/files/9bfc6e63bfca00343160a96e7eb2c94b/36680982842.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160d5d35645274---84925281172.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160817360aa27b---65535907617.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/5a5b75a528913b3018a59af075c17bde/56462218309.pdfIn PDF document text
    • http://doggystylzgrooming.com/admin/photos/file/32638146914.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/145a4c795785e3f00d0bd3faa7c863ab/kuzozakovapuponajapi.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/8lc92sn2oaogqtq7a90pmpl4f9/18307850753.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=system+theory+in+management+pdfPDF link annotation
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/f6ba82983319200a133b8abaa170eb35/tuxajusuku.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_off0000e23c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE23C 11088 bytes
SHA-256: 7fb0217a714b12312443c78eb3d3f5ce38d5205285b7a75244ae4b75aaff847e
font_01_sfnt_off0000fbb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBB0 15868 bytes
SHA-256: 621cae73ac49e2d5ba05a673feadb926d794a6e32a92290b159ebbc0b8cee49a
font_02_sfnt_off0001246a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1246A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1