Malicious PDF — malware analysis report

Static analysis result for SHA-256 55c71c944d2e9bc2…

MALICIOUS

PDF

81.9 KB Created: 2021-08-16 02:28:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 47a65db3ba8f0fd0cb3d09dd556c9128 SHA-1: 1f1cf54788653ce349e4dd3737e6d5c8e5879e83 SHA-256: 55c71c944d2e9bc2a8dc00182118bf0153eb4caf2349fa491d8412de50399493
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URLs, many pointing to compromised WordPress sites, suggesting it functions as a link farm to distribute malicious content or phish users. The presence of embedded URLs and the overall structure point towards an attempt to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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 https://inwebjor.ru/uplcv?utm_term=bekhayali+song+download+pagalworld+video PDF link annotation
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609a1909bf55b---59806922291.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16091c74d888bf---19800384289.pdfIn PDF document text
    • https://yucekalipmakina.com/tsrm1/img/userfiles/file/26137373083.pdfIn PDF document text
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/mes22vlc9pbnrqr55s7tmifng1/padodezuvurezuni.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160862eb45ad30---53419274551.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b99e3cf06f5---22789815985.pdfIn PDF document text
    • https://actor-conseil.com/files/file/sinumipexajiwalepaga.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/60e9b94386c083062599ff1768a63837/mumeji.pdfIn PDF document text
    • http://locthanhwindow.com/img_duhoc/files/wijumetimenazuzev.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/b3443eef8da1534235384acf6390b048/82974437431.pdfIn PDF document text
    • https://www.peltonfell.org.uk/ckfinder/userfiles/files/29850014778.pdfIn PDF document text
    • http://diversecityuk.com/userfiles/file/momitedenipa.pdfIn PDF document text
    • http://rcp-ranstadt.us/files/51695818692.pdfIn PDF document text
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/f3c2fd13018027a37fdc6c4b26975beb/48921868793.pdfIn PDF document text
    • https://noihoithanhtuan.com/media/ftp/file/23202662294.pdfIn PDF document text
    • https://comobrew.com/newsite/images/user_uploads/file/48394877025.pdfIn PDF document text
    • http://concept-art.nl/app/webroot/files/userfiles/files/95216233186.pdfIn PDF document text
    • https://www.prestigeautobody.com.au/wp-content/plugins/super-forms/uploads/php/files/f49ff19ed158adb414de08ac9c584f21/85424022008.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1611704d330247---kegujotupu.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cbfefb3c2b5---67509351848.pdfIn PDF document text
    • https://www.naabelectric.com/userfiles/files/37624240820.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bedd2e1c3f9---folegiwu.pdfIn PDF document text
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/cdb542e00f6597959c44387106c4f0bb/dowupusolijufaniteruk.pdfIn PDF document text
    • http://debden.org/userfiles/file/64370701103.pdfIn PDF document text
    • http://kfnmdg.com/upfolder/e/files/20210705150055.pdfIn PDF document text
    • 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_off0000dd56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD56 16416 bytes
SHA-256: 24b179f2e7fbdf755a698396d1a7121c2e3a1814e2f0481f0bd8a2084f0ffa75
font_01_sfnt_off00010806.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10806 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001201d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1201D 10984 bytes
SHA-256: 54b7146dfabf5db720f1c4bca5252dd5f097194812cf98089c62acd7f55067b3