Malicious PDF — malware analysis report

Static analysis result for SHA-256 b381b031cb291d1b…

MALICIOUS

PDF

95.8 KB Created: 2021-07-08 07:13:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: af7097a9011c2628428ed52a85085f3b SHA-1: e31ce9512a747590b5674fda253a2d61a122edf7 SHA-256: b381b031cb291d1be80c2fe3c4909997bde862d709d9053efda061f1b2119380
156 Risk Score

Malware Insights

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

This PDF was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs pointing to compromised WordPress upload directories and disposable hosting sites. These links likely serve as a distribution point for further malicious payloads or phishing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://easternsheep.by/app/upload/file/levetixo.pdf In PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a406c4a980f---9819738781.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/ukdekmbthklasqm3cpb3essh5k/19581790555.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/leu9itj3engk75e4nan790kgh7/52773358362.pdfIn PDF document text
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/8da4602ada0b61eaa7e83b9948b58afc/84539179422.pdfIn PDF document text
    • http://musikpark-live.de/userfiles/file/julebukemijobalijarew.pdfIn PDF document text
    • http://almar-bus.pl/userfiles/file/45416061875.pdfIn PDF document text
    • http://chhsclassof70.com/clients/1/1f/1f6d1b94cf555b90b9f410dfa82aea5f/File/94262225358.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/9d6694688dd6829c7d523cc3bf71a487/zedawegakijivezudixu.pdfIn PDF document text
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/7efd0ef1addc79fc89c05b87f9f19b7b/21123821407.pdfIn PDF document text
    • https://congchung7.com/upload/file/82340868145.pdfIn PDF document text
    • https://coloreverything.love/wp-content/plugins/super-forms/uploads/php/files/ab146624d5d99e8a19cd49114df01008/21920316456.pdfIn PDF document text
    • http://bona-agra.pl/Upload/file/rizazojoxov.pdfIn PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/vd9t6p2m36r40u2p2jtcbebvke/20300011889.pdfIn PDF document text
    • https://binarbaid.com/public_html/userfiles/file/99440280388.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160962d12bb1ec---9008027192.pdfIn PDF document text
    • https://argumentua.com/i/file/61495640449.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/338a7320bbc3ad821fc553088faa0105/subisunofawagidedetiwe.pdfIn PDF document text
    • https://mps-india.com/userfiles/files/dawinewuzenu.pdfIn PDF document text
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16085e4d38a02b---40290896866.pdfIn PDF document text
    • http://studioagronomoserragiotto.eu/userfiles/files/bajozeze.pdfIn PDF document text
    • https://daleel.global/wp-content/plugins/super-forms/uploads/php/files/1ej0fpkrnpb3fr8q80ba4mqcdp/29535536398.pdfIn PDF document text
    • http://asustainable.com/global/file/vejidatav.pdfIn PDF document text
    • http://samnakthodrahassob.com/userfiles/file/13597849231.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=faith+evans+todd+russawPDF 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_off00011287.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11287 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012a9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A9E 10528 bytes
SHA-256: 6ef3ff3faea297921b9178d8e1d68021a36c8274dd0fd66115a93eea6cc63119
font_02_sfnt_off0001429b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1429B 17644 bytes
SHA-256: ce4b53bc3b4542702f1c6f51b8cb2e33f01399547d153f2ce2fff2a7a1e6f746