Malicious PDF — malware analysis report

Static analysis result for SHA-256 31bb42322bcedad8…

MALICIOUS

PDF

83.4 KB Created: 2021-09-09 23:46:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: ad15a3a2140a56ce1c1c46c500fe7ead SHA-1: ac2cd68036e7a5d7d6720c342800c4017087cfb7 SHA-256: 31bb42322bcedad89ea330555950f8663f5f06544ab909c82bb89c18ce655d1e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/161312c53d60b8---53443993654.pdf In PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/ob5ug26lcep8gsnphrkp2uain0/48665696213.pdfIn PDF document text
    • https://happy-playground.gr/uploads/_uploads/files/47726025186.pdfIn PDF document text
    • http://chapelguild.com/images/usr/veminetok.pdfIn PDF document text
    • http://assisdrive.pt/userfiles/file/13358797100.pdfIn PDF document text
    • http://studiotecnicobergamaschi.it/userfiles/files/63376516966.pdfIn PDF document text
    • http://fgosvo.ru/files/files/papiwigekagetegolino.pdfIn PDF document text
    • http://iburgisidimarsala.eu/userfiles/files/51811318287.pdfIn PDF document text
    • https://aglogistics-bo.net/userfiles/file/74960306175.pdfIn PDF document text
    • http://myxroad.net/upload/userfiles/file///wisexasadib.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/161350869af5b6---13663403954.pdfIn PDF document text
    • https://colakcivi.com/userfiles/file/fuxuwi.pdfIn PDF document text
    • http://busangh.com/attfile/fckimg/file///2021090675420_702731060.pdfIn PDF document text
    • http://metall-press.ru/files/rebegikudeboneto.pdfIn PDF document text
    • https://dananeye.com/uploads/files/202109031305155509.pdfIn PDF document text
    • http://tevukasveza.lt/ckfinder/userfiles/files/56312892598.pdfIn PDF document text
    • http://valdhans.cz/userfiles/file/39146308803.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/a39fe021eba93eafca25d9d409ba69f2/zelomerebisel.pdfIn PDF document text
    • https://partnyor.az/userfiles/file/jexigovorajajorosovoloziw.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/08ed3e6d8a099216fa58688a5c1fa6c8/5890135018.pdfIn PDF document text
    • https://srilangkapools.com/contents/files/10725238266.pdfIn PDF document text
    • https://zenithoverseas.com/assets/userfiles/files/zumapo.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1613a176f4c5d9---78030264575.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=what+is+amber+alert+on+my+phonePDF 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_off0000e2dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2DD 10764 bytes
SHA-256: a87a808d58fb050be4894250afe11fcd2a9dd5dfbeb0101072b3db9b2412dde4
font_01_sfnt_off0000fb3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB3C 17344 bytes
SHA-256: 0b3f8c1ac21ae641579d9215d573bee018a09659ea7440532c6a73c5eb201f69
font_02_sfnt_off000127dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1