Malicious PDF — malware analysis report

Static analysis result for SHA-256 a08def0aa000d135…

MALICIOUS

PDF

82.4 KB Created: 2021-06-27 07:34:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 392ef9f764eac3717ed2fa47e37c287a SHA-1: 57a4b7f236e501c73bc7c7ce89e9207a0815cc33 SHA-256: a08def0aa000d135ebca98ab240be85b6eee3dbb76969ce4a7788228a216d96a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on compromised websites, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://archism.ru/uplcv?utm_term=achilles+tendon+sore+to+touch
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/cbe471c1f19fee8c17055935a1d6a3a2/30972737759.pdf
    • http://maynenkhipuma.vn/quangbasanpham/app/webroot/upload/image/files/gajinonarer.pdf
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606c95251561c---zowenenabozatoxugid.pdf
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3b3f242644---61739231113.pdf
    • https://schmitz.cz/res/file/39777344153.pdf
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/82ea83559ce4f8493b7d68cf71bb2239/nikisusupinufonukirogu.pdf
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608523f0df6e1---lowojo.pdf
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/160723d44908a6---xerilejokibes.pdf
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/e165e156d301fff8fbb80f149be5ef7a/40808494164.pdf
    • http://goldnumber.info/userfiles/file/45519634073.pdf
    • https://autoradiator.mn/uploads/ckfinder/files/26025299774.pdf
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a242634cdad---23977591794.pdf
    • https://trungtamgiasuhcmmq.com/uplaod/quangtri/files/wenoxexamigekokadozif.pdf
    • http://mmckno2010.zkosuchdol.info/files/34686048790.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a278c7459e9---girudaveb.pdf
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c79b0b5a198---48947728305.pdf
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ace93ded793---puweb.pdf
    • http://tachikawa-derma.biz/ckfinder/userfiles/files/neredosufas.pdf
    • http://shqinze.net/admin/upimg/file///netalozizidusil.pdf
    • 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_off0000e275.bin
3c2e2b3f06b1271e8de85a866ba1a11993f54ac3893950ce0ea0350a3124739b
pdf-font-stream PDF embedded font (sfnt) at offset 0xE275 16488 bytes
font_01_sfnt_off00010d12.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D12 16792 bytes
font_02_sfnt_off00012529.bin
a26481a979991b22b3cb1284419838334126d6631a4876484f715c813ca6d8c0
pdf-font-stream PDF embedded font (sfnt) at offset 0x12529 10384 bytes