Malicious PDF — malware analysis report

Static analysis result for SHA-256 90e699bc6e2f701d…

MALICIOUS

PDF

94.7 KB Created: 2021-07-30 06:25:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4d9b1d55fd44026fc10e9dd0b5b0be04 SHA-1: 997927c9ec20dbc81b3354307411226635bf5e61 SHA-256: 90e699bc6e2f701da78209b2b5101a6351d85150bd6918d4f072b11cdd0d6829
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains a large number of embedded URLs, many of which point to compromised WordPress sites, suggesting it is part of a link farm or phishing campaign. The document body is heavily obfuscated and unreadable, but the presence of numerous external links indicates an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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 https://chcial.ru/uplcv?utm_term=clash+of+clans+farming+attack+strategy+th10 PDF link annotation
    • https://awlights.com/wp-content/plugins/super-forms/uploads/php/files/f990bc998b3d41eb0c8c8929b6f3f5d5/vumalobidujuxitorovukas.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8891969e34---28012959219.pdfIn PDF document text
    • http://kameleonhastanc.hu/files/file/80049938908.pdfIn PDF document text
    • http://velo.hu/UserFiles//file/5781023181.pdfIn PDF document text
    • http://indel.sk/userfiles/file/64862589054.pdfIn PDF document text
    • http://fkhd.cz/data/img/kovemegusaxuzejokag.pdfIn PDF document text
    • https://gw21.ch/uploads/userfiles/file/1346472512.pdfIn PDF document text
    • https://olterus.info/contents//files/66199345904.pdfIn PDF document text
    • http://fruitvita.com/files/files/9011056362.pdfIn PDF document text
    • http://uci.ir/userfiles/file/56818225462.pdfIn PDF document text
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/16249662143321.pdfIn PDF document text
    • https://aspaeng.com/files/image/files/30725139123.pdfIn PDF document text
    • http://bpsstudio.hu/uploads/67099905422.pdfIn PDF document text
    • http://imi.vc/upload/files/gadupajamirinusili.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2c21ad4899---14184433946.pdfIn PDF document text
    • http://sgadsahodayatarntaran.org/sahodyatarntarannew/userfiles/file/berukiwogirewi.pdfIn PDF document text
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/364f48ec4e721f967d2cfbbae0d34296/76889266512.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160d97414061ae---98702275264.pdfIn PDF document text
    • https://classconnbio.com/img-jacson/files/28496681265.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/e6397efc79155e9345424629652989aa/26778990628.pdfIn PDF document text
    • http://mwcapital.net//ckfinder/userfiles/files/59446574728.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_off000104b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011cc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CC5 21304 bytes
SHA-256: e3effa482a2ca341298a3432959661c01547e44580b2514d7ffb344b3163d14f
font_02_sfnt_off00015180.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15180 11192 bytes
SHA-256: ac868ba5263f8201332110390135936176e828b139fac7c5e0b7904ddf63f411