Malicious PDF — malware analysis report

Static analysis result for SHA-256 f41bef2cfc8c6536…

MALICIOUS

PDF

86.9 KB Created: 2021-09-04 07:02:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 2b5b9d9ca9dfcc6d1e2ba2f2e33349c3 SHA-1: f08794c88883815c52fd6852ad141d309140ce71 SHA-256: f41bef2cfc8c65362931f25da65e97b698c001d9db00540dbd04b755435faebf
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond what the heuristics reveal.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9946

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://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160d1b5cdee17b---wefidezad.pdf In PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160b310cd6ec7f---40334223365.pdfIn PDF document text
    • http://reversetheclocknow.com/ckfinder/userfiles/files/wuduviruwixusowo.pdfIn PDF document text
    • http://falconartistmanagement.com/ckfinder/userfiles/files/relati.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/27di2du6hapsjve04tsbvlpsr5/kalejuziget.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/160766b2becd0e---60711519958.pdfIn PDF document text
    • https://mdteam.se/ckfinder/userfiles/files/5250771057.pdfIn PDF document text
    • http://residenceraffaellotorino.com/userfiles/files/xagasaduviribanukukina.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/160a819fad77c1---96205504718.pdfIn PDF document text
    • http://indianspringhomes.net/userfiles/files/78277392672.pdfIn PDF document text
    • http://telekommarketing.com/firme_data/files/68526030346.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a866f6a91fe---budakevodugim.pdfIn PDF document text
    • http://felixefontesadvogados.com.br/ckfinder/userfiles/files/pogeloforewepubewetelabar.pdfIn PDF document text
    • http://abcbyspu.net/ckfinder/images_store/files/tadukasewapibijerogepulem.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16116d316f0d08---18121202517.pdfIn PDF document text
    • http://itemclinicchina.com/ckupload/files/86750867859.pdfIn PDF document text
    • http://mamnonkitty.com/webroot/img/posts/files/vuvagoxasagorufeju.pdfIn PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/fembu47ofi3arrbmgi5kn6lck9/9366716003.pdfIn PDF document text
    • https://wendi101.com/userfiles/file/89652067557.pdfIn PDF document text
    • http://zuestag.ch/userfiles/files/puwonizuwiv.pdfIn PDF document text
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/25881cc3f0576bdb4993ca949243f33c/xobopepi.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/75464235959.pdfIn PDF document text
    • http://allprintusa.com/admin/images/file/89307316218.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16089921fea5b0---84577085352.pdfIn PDF document text
    • https://abzesolar.com/uploads/files/feledigox.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=meaning+of+emojis+pdfPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d76f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD76F 16576 bytes
SHA-256: abfb7bbc5ae0e5fff220c31dfbf06b51cd2bf098c9d55587bed44f415c7849b6
font_01_sfnt_off0000ee10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE10 18204 bytes
SHA-256: 3d2bc93392d00b6fad7035eedbcf77c420ee6fb8325df833c7c6811014d66d4f
font_02_sfnt_off00011cfa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CFA 10720 bytes
SHA-256: 8d379b75f790fa6094a93ba046ea2fd1663c333f91a79d3cbe4535882b8f68ca
font_03_sfnt_off0001354d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1354D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1