Malicious PDF — malware analysis report

Static analysis result for SHA-256 c957e6a2d5b0b5b7…

MALICIOUS

PDF

82.4 KB Created: 2021-09-20 14:10:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 07d378f0c29a4d7f815aed3114faa461 SHA-1: 86ad0b1ae85c34c61697ce4cb88026a71bf339c8 SHA-256: c957e6a2d5b0b5b7fbe4195d737ca1ac9d0bd1119fb7014c3fbeecd513556166
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm hosted on compromised WordPress sites, a common tactic for distributing phishing content or second-stage malware. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to malicious content, likely involving JavaScript execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613fa3cc40e2c---susojonuwaraponefiki.pdf
    • http://angelojrobles.com/admin_initial_test/userfiles/file/paluvumozawagadidu.pdf
    • http://dekobonner.de/userfiles/file/41948200630.pdf
    • http://www.workbythai.com/admin/assets/images/71493870832.pdf
    • http://falerisztika.hu/tmp/dezepewunujixevurubatumu.pdf
    • http://apexnepaltravel.com/userfiles/file/momajapimudulopejavut.pdf
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/18367fef7495f3c7f8558c46aa3307b1/sexigadaxaro.pdf
    • http://www.novosib-sport.ru/ckfinder/userfiles/files/84619668245.pdf
    • https://nationalshield-uae.com/userfiles/files/bedur.pdf
    • http://p-energo.ru/content/file/58200652156.pdf
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16138ce4c05219---7165035901.pdf
    • https://www.singaporemedicalclinic.com/ckfinder/userfiles/files/97178003102.pdf
    • https://afmiletisim.com/resimler/files/49669346847.pdf
    • https://ptkas.com/kingkong/userfiles/files/58133541910.pdf
    • https://paymentor.nl/uploads/file/rakimupudiwapujapupuka.pdf
    • http://sofia-es.tokyo/yamituki-n/uploads/files/99322367671.pdf
    • https://jcmimoveis.com/userfiles/file/razevulipiv.pdf
    • http://malerbetrieb-malanders.de/Webseite/pics/fotos/1/file/55252582324.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e98596993e---38311608154.pdf
    • http://rtm-plus.com/ckfinder/userfiles/files/tijojewaru.pdf
    • https://redengewinnt.com/userfiles/file/64810790446.pdf
    • http://buzmakov-ua.ru/admin/ckfinder/userfiles/files/rezetiv.pdf
    • http://ipceurope.be/assets/file/32923832025.pdf
    • http://lukasikgroup.pl/Image/files/xisonakun.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=slow+mo+apps+for+android
    • 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_off0000d9f7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9F7 16792 bytes
font_01_sfnt_off0000f20e.bin
3495a6c7f179a29a8f5212d10a928c01d90549407df2673ed55b9cd809efa5eb
pdf-font-stream PDF embedded font (sfnt) at offset 0xF20E 10588 bytes
font_02_sfnt_off00010a29.bin
00d440e40f9cc52026f62a497322ce67c638c8350f4ffb733913f1a219db4c83
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A29 19120 bytes