Malicious PDF — malware analysis report

Static analysis result for SHA-256 f685e0226c644fe1…

MALICIOUS

PDF

77.9 KB Created: 2021-08-28 17:23:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6e4209e29b47db8e10f192d6fed0ab5b SHA-1: 796149e33ec36d96ed6a3d51d50be1928b1f32b2 SHA-256: f685e0226c644fe11d1e4562b24fb878f34c4507e47bd061ee1e52ba44628203
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external resources, many of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution through these links. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/160bb56ca24d13---juredanunidizab.pdf
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/8ba75f6a1373a6addd3d2237b235ab47/xedozozedojilewifu.pdf
    • http://ip-golubev.ru/ckfinder/userfiles/files/55538635670.pdf
    • https://corianderedmonton.com/ckfinder/userfiles/files/jefawowodafoduziwin.pdf
    • http://mhspartan79.com/clients/9/97/97d0d0788ec4d6723ba7be3cd58769e3/File/82182483784.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/g0aem5t3hb7hfatb55cggfdun1/rajazelurababuvapif.pdf
    • http://guojingmall.com/userfiles/file///pewilakubawatolosisu.pdf
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16076afa26cb9e---59257127473.pdf
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bb2a5470d2---pikupikazivozude.pdf
    • https://interstudy.net/userfiles/file/pimufikomuvoz.pdf
    • http://www.radiooro.com.mx/media/images/uploads/files/gavegovetef.pdf
    • https://a2designbg.com/userfiles/file/vesegapisim.pdf
    • https://inverpalmas.site/aym_image/files/petepuwawanilimipi.pdf
    • http://maynenkhipuma.vn/quangbasanpham/app/webroot/upload/image/files/sunugikoturikus.pdf
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c0525ba4c52---8495093813.pdf
    • http://csc-028.com/userfiles/file/20210612080657_2et8t6.pdf
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160826526ca395---degatulazo.pdf
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/1609ae0a534db5---duxetopadijasalepifu.pdf
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c84dd81a38c---sufabikasunotox.pdf
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ce1af0c312d---6235626842.pdf
    • https://cuacuonbentre.com/upload/files/tizonivojapozoduwute.pdf
    • https://unosms.us/userfiles/file/sawenususalikafoxa.pdf
    • http://gbfrjournal.org/pds/userfiles/files/23369767952.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=terence+stamp+miss+peregrine
    • 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_off0000ccfe.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCCFE 16792 bytes
font_01_sfnt_off0000e510.bin
2bfd2e430dc326673109ca0500571bbc8b4b4706f648352e6ae09f581a259f43
pdf-font-stream PDF embedded font (sfnt) at offset 0xE510 17404 bytes
font_02_sfnt_off000111d6.bin
443dc90a6d136a72318e91dac09e31ecb879c0a2df1e638108e7cd95c9c76315
pdf-font-stream PDF embedded font (sfnt) at offset 0x111D6 10516 bytes