Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f817135d2e07963…

MALICIOUS

PDF

80.6 KB Created: 2021-08-29 14:59:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 57c9641e8404e2c55e09059632eca58a SHA-1: f45787de1ff12700aa92078011c707bcae5ef60b SHA-256: 3f817135d2e079638a6e59ecede4d6336955597d193356894eced4bde86e0feb
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites, indicating a link farm or phishing lure. ClamAV detected it as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The document body is heavily obfuscated and unreadable, but the heuristics strongly suggest malicious intent through link manipulation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/d1ff9a3cf2dd212bcb8ebb6394537b63/vutesefajix.pdf In PDF document text
    • http://cafehinglung.com/uploads/files/56716543508.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/2bl644b3gs70foeuacr9kmpb67/21313827631.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b061604bf41---nivefusijujikuzevavaguw.pdfIn PDF document text
    • https://solturism.ro/images/file/11742342498.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/sigelijaj.pdfIn PDF document text
    • https://marblobaths.ph/app/webroot/img/files/sesadijadumomibakivu.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/re3etnn3pfa7vu0hp9t5v7uhl9/zigajaku.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/aa88b3bfed342496346c12ff04bc648c/gogokipikaxerago.pdfIn PDF document text
    • https://thic.muki001.com/plugin/ce1/ckfinder/userfiles/files/zekuxunolopejevin.pdfIn PDF document text
    • http://hilimall.ae/uploads/files/95719219514.pdfIn PDF document text
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/0f741aff04583a821132458e126247be/4589325918.pdfIn PDF document text
    • http://v-lukomorie.com/uploader/files/nutamaleme.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608be5ccf153f---94389584392.pdfIn PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/72b862eff487d10524d2325979be23cc/senosetadadexoxinologibi.pdfIn PDF document text
    • http://westpakusa.com/phpsites/vertical_living/uploads/file/10023677864.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160d3d22270b1d---4232573298.pdfIn PDF document text
    • http://narcisse.sk/editor_uploads/files/12272691962.pdfIn PDF document text
    • https://cardion.dk/gfx/fckimages/file/jimotomupekerofadu.pdfIn PDF document text
    • https://prestinieurope.com/userfiles/files/tivovakewefiso.pdfIn PDF document text
    • http://edv-denk.com/userfiles/file/42687706449.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/160753ffb5b788---posakijinowasubuvepik.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094366c7a231---82854110484.pdfIn PDF document text
    • http://agendatourvietnam.com/hinhanh/file/29460652338.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=top+rated+hand+car+wash+near+mePDF 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_off0000d4ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ecfe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECFE 17580 bytes
SHA-256: 8ab5acc8910f53cbbebcb561110ced0b41aabc49ab772fc5792adc8111860e9f
font_02_sfnt_off00011ac9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AC9 10692 bytes
SHA-256: 9bdf0c6f349970a1151bcaaa30bc92130f20cc9a20162ef36a27256c8f2ff680