Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a66b8eec6571a80…

MALICIOUS

PDF

93.9 KB Created: 2021-06-29 21:08:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 00923b1233b30403310900e260699083 SHA-1: 9969cffaab88f50f424a76624bff755f2dbcf54b SHA-256: 7a66b8eec6571a80cdb0da8b1316cc0ca5ef1c86da300bf155d3f1101299f6e1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm directing to multiple compromised CMS upload directories, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document's structure and embedded links are consistent with a tactic to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://tjsijiqing.com/ckfinder/userfiles/files/2021/0609/eb035d7880179d8d6d58a75df50c6df7.pdf
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dda092ac02---82954297717.pdf
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16079364e3cb38---23171018334.pdf
    • https://www.bocamvigliesrooms.com/wp-content/plugins/super-forms/uploads/php/files/403708d03d013df2fec9ee0f21461f16/xigowazonare.pdf
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/625c72a5bf0edc8dfcdf401b34c2d533/6521397868.pdf
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609090ce1528d---66002712790.pdf
    • http://vaikevai.com/ckfinder/userfiles/files/kumerogugalebasizoxok.pdf
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b83cc9c064e---duxivimeworotutizofipima.pdf
    • http://aite-materials.com/upfiles/file/46037404269.pdf
    • https://xn--faades-mtal-n9a6a.ch/ckfinder/userfiles/files/75561275156.pdf
    • http://divorce-difficile.fr/userfiles/file/21350123241.pdf
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/49f2fb063bdb51e2beeee88c782be6de/vagepux.pdf
    • http://aktifbant.com/resimler/files/32064858241.pdf
    • http://healthywithhart.com/res/file/21377311376.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160955d6664052---89624693950.pdf
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a18be927f9e---titakufo.pdf
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bad425294ec---12813672624.pdf
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/1608aa328817d6---xidobawuvanabudubomo.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160984a8442849---nejimaloxegozujirike.pdf
    • https://scanclean.bg/upload/ckfinder/files/wunifem.pdf
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a4a18e47748---wulepit.pdf
    • http://reicar.dk/userfiles/file/2594135065.pdf
    • http://architettotamborra.eu/userfiles/files/43036349054.pdf
    • http://nfc.soo.jp/file/73429821637.pdf
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16088eabbdebd1---radumotizijunelibuzub.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=new+home+my+excel+23l+manual
    • 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_off0000feff.bin
0d1fef8df44ad5b54b47a5819514ebfc7ee3d287a0f8e61face594a084677000
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEFF 22820 bytes
font_01_sfnt_off0001380b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1380B 16792 bytes
font_02_sfnt_off00015022.bin
3bd383bbb340a8aae20e744794487115643a7d434009b2ae8f00efc11479e508
pdf-font-stream PDF embedded font (sfnt) at offset 0x15022 10708 bytes