Malicious PDF — malware analysis report

Static analysis result for SHA-256 57bb26cc44eb62d8…

MALICIOUS

PDF

89.2 KB Created: 2021-07-26 01:55:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fa3021ae0c61e47e39467a4f0e1ab58e SHA-1: 301b2b116894dc06d06464456377a13cda46c5ef SHA-256: 57bb26cc44eb62d8e69ab1f3d99846c039be0aa4f153fa889525ef0dfcf03342
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document that exhibits characteristics of a phishing lure, as indicated by the 'SE_INVOICE_LURE' heuristic. It contains numerous embedded URLs, many of which point to compromised WordPress upload directories or disposable hosting, suggesting an attempt to distribute malicious content or redirect users to phishing sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely involving the download of a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4f43cd04cd---68256652769.pdf
    • https://fresh-cherries.com/ckfinder/userfiles/files/99248074406.pdf
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/54705e1f179e91066dcd9939f8c37108/zominoresoluta.pdf
    • http://jhdljz.com/userfiles/file/1626733903.pdf
    • https://piataafacerilor.ro/app/webroot/files/userfiles/files/98978395733.pdf
    • https://cengilli.com/icerik_images/file/vigerebimaruxonutokiza.pdf
    • http://italiangreyhound.pl/img1/userfiles/file/mozitixak.pdf
    • http://aliceinformaticasrl.com/user/pages/joduzirejumagixiselex.pdf
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609479ffac021---pikosomitibutenal.pdf
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a08afbe1226---31908998733.pdf
    • https://nistd.in/userfiles/file/sebapokadapatobiriruxu.pdf
    • http://sahrugs.com/userfiles/file/26120375670.pdf
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160a220a0f0bee---24343796319.pdf
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ae38dde957d---25815353293.pdf
    • http://jngf.cn/files/file/63515429106.pdf
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160841b6dec31e---96891713929.pdf
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b38e4e05b2---lepejupifu.pdf
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b3405a0f1b6---22122777344.pdf
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/cc0a7425f86c48394bb4db1f2e264903/wedekalipugofubog.pdf
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/b8713034c23a93882147b065e7208cd9/60221801032.pdf
    • http://diagnosticaedilizia.com/userfiles/files/mexibajagabejifegiwev.pdf
    • https://eminenceconstruction.ca/viking1/uploads/files/dugupever.pdf
    • https://sharadsangam.org/UserFilesTwo/file/25837830853.pdf
    • http://dancephoto.ru/userfiles/files/datuwediwagatotaj.pdf
    • https://okazionche.com/files/90673724439.pdf
    • https://csodamalom.hu/files/files/losanuxixibuvil.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+write+a+contract+to+pay+back+money
    • 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_off0000f89e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF89E 16792 bytes
font_01_sfnt_off000110b0.bin
c62dd249466e6b232a41006bd8294b6f322cfcfcee2e3bfdf100b63951ee8f5a
pdf-font-stream PDF embedded font (sfnt) at offset 0x110B0 17240 bytes
font_02_sfnt_off00013e1b.bin
2b42c01a9ca4d535060775cd55734002b100d52ee3759bde7468b0de209550df
pdf-font-stream PDF embedded font (sfnt) at offset 0x13E1B 10744 bytes