Malicious PDF — malware analysis report

Static analysis result for SHA-256 c994892dd08e156c…

MALICIOUS

PDF

82.4 KB Created: 2021-08-26 22:53:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 040f90c35093a3d2ea1bcc1a6f862ebc SHA-1: 10a80046706da7b5ba5cefc58806f2cb54455a28 SHA-256: c994892dd08e156c895855ca4dd95bd1d56e34c967faa79f1520f5f7fe678d97
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file that contains numerous links to external websites, many of which are hosted on compromised CMS platforms or utilize SEO link farm techniques. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded URLs suggest an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/ab38236a8080bcf1bcdd6f0704bcd537/16933529697.pdf In PDF document text
    • http://lucidarepavimentimarmogenovaealessandria.it/userfiles/files/48197217126.pdfIn PDF document text
    • http://instandee.com/Images_upload/files/sinaxusuwivifino.pdfIn PDF document text
    • https://apc-algercentre.dz/ckfinder/userfiles/files/karifexipebodovizid.pdfIn PDF document text
    • http://a-swiss.com/upload/userfiles/file/doxateviranokazu.pdfIn PDF document text
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/3930a45d657231635f2b111d93eeccaf/10336299858.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/2209741837.pdfIn PDF document text
    • http://tasarimak.com/ckfinder/userfiles/files/37338885528.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c88a7916b3---63241914134.pdfIn PDF document text
    • http://rbc-bezorgdiensten.nl/upload/67461094915.pdfIn PDF document text
    • http://cricalliance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b9d3a7c73e---25137348288.pdfIn PDF document text
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/d4uodqvm1n5c0u0cr4h4fdeip2/97844006302.pdfIn PDF document text
    • http://lakshimi-kaatsu.com/user_data/packages/default/imgfiles/soderimikajelatopokuk.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/2d86so5cvg1qqh8derk5v48kb7/jalirates.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a63d05511---dozenusufesagulilizuludeg.pdfIn PDF document text
    • https://livredart.com/ckfinder/userfiles/files/wodimukavoxuwo.pdfIn PDF document text
    • https://macroedunet.com/userfiles/file/nuripenazumifumuded.pdfIn PDF document text
    • http://blackshirts1961.com/clients/7/71/7137ee3fbd99c17d296746b31d66a47b/File/bopolagupax.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-5-25/20210525165537786364.pdfIn PDF document text
    • http://corporacionnoa.com/UserFiles/file/nuwubevigaderabipimagusuj.pdfIn PDF document text
    • http://cukiernia-waltar.pl/qcms/userfiles/file/26902796024.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/6uk3mveb2qa392t1fa6546v0m5/68771767765.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6ba50c9964---suvoxolorogozuze.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/xuxamume.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd29089ce9---nixodogu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=noughts+and+crosses+game+onlinePDF 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_off0000de7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE7F 10896 bytes
SHA-256: 6a9cd26cd7f5f1822e15e45c81e89a2e4f8fbfe906f150c36bae3f4466040045
font_01_sfnt_off0000f74a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF74A 16876 bytes
SHA-256: 8a444c1093f79512d42b6c4500b5d415e15bed8e7176079d1786db8ac2da1b42
font_02_sfnt_off0001234c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1234C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1