Malicious PDF — malware analysis report

Static analysis result for SHA-256 27c8d2d8437c495b…

MALICIOUS

PDF

89.5 KB Created: 2021-07-05 17:52:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 56e863a17982249c7d9efd6522ab0466 SHA-1: db5b7a2187e7d119a3302a82cb6f32b156fd2a91 SHA-256: 27c8d2d8437c495b3d5446278068bf0da0fc293f904bb5f1980869a490e6fe38
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

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 CMS uploads and disposable hosting, likely to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues to its specific purpose beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://gregor-biffiger.ch/userfiles/file/17262583021.pdf
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbb883506a9---gekipa.pdf
    • http://www.kickcommerce.com/userfiles/file/lasipawirenazoxamowigef.pdf
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609840f9861e1---34670406742.pdf
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d5815a188d5---sawame.pdf
    • http://ricarda-allegra.de/userfiles/file/73100949427.pdf
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/v2t5lgihkjsc807pp88cbitbpb/duxogarozesuk.pdf
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a01a74be79---junonekizarivisogo.pdf
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/dg1ebga8fveh4ejbn7q7enn4r6/wapanewabaketajeromexesi.pdf
    • https://suativisamsungtaihanoi.net/upload/files/tififelekebiledalifidaju.pdf
    • https://betalinktech.com/blmedia/file/70489906164.pdf
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086067cdc8c6---5413962100.pdf
    • https://carstenrath.com/wp-content/plugins/super-forms/uploads/php/files/4eletll1u605e310j5i64m5l0j/31244345.pdf
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/1b6c319de299cbce8be7a0918ddbf23e/3376560290.pdf
    • http://www.minaakshimajumdar.com/fckimages/file/lamofesa.pdf
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/a498839fe1771a57e490ec564bbe4165/53537619248.pdf
    • http://xiaohecollege.com/d/files/vobugolug.pdf
    • http://bachova-terapia.sk/images/file/88161123581.pdf
    • http://hopkinshigh62.com/clients/7/77/7764523e397120ad9b09b1da26998858/File/rezufuf.pdf
    • http://atek-ent.com/upload/file/fuduvufabevek.pdf
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/decfbd3d0c267fec2fce818b5bdf34a1/burajedoxaju.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608996914467b---dejisikufosoxak.pdf
    • http://meble-tk.pl/userfiles/file/40683069658.pdf
    • http://golden-candies.ru/webroot/files/files/goduxusuteditubutawoke.pdf
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607875870d3dc---13106833476.pdf
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/oomh0i53uei5ln12096ujgjr4j/fomatofodare.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=the+wish+giver+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_off0000f8f5.bin
9f37622ed9ce9458b13060f01a6d342142d7ef640417eeacf55c5bd4d9c4a176
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8F5 17932 bytes
font_01_sfnt_off00012801.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12801 16792 bytes
font_02_sfnt_off00014018.bin
2dc02ad221d6fa47c208783e2d49f89c6b04662427dd61f6d6e944a9088a6d2b
pdf-font-stream PDF embedded font (sfnt) at offset 0x14018 10364 bytes