Malicious PDF — malware analysis report

Static analysis result for SHA-256 839478a10425450f…

MALICIOUS

PDF

85.0 KB Created: 2021-07-04 04:54:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1e9c578268100f76e3f2a2a02ce07535 SHA-1: 820131d715188f22b058577145f4ea16f6c0a2fb SHA-256: 839478a10425450f4a5537cf4d0337ef59592416bd68545b6401102ab263d466
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating it likely serves as a phishing or malware distribution lure. It contains numerous external URIs and links to compromised WordPress upload storage, suggesting it is designed to redirect users to malicious sites. The file's structure and content point towards a link farm attack pattern, potentially leading to further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://crysiq.ru/uplcv?utm_term=preposition+exercises+for+class+3+cbse
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1608c99678fff8---69182028534.pdf
    • http://3bbb.fr/ckeditor/upload/files/famofozijafiladezesile.pdf
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160b056e61cd17---93861930335.pdf
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/ds0e68ggtfgkjceejlrs9gmksn/migidij.pdf
    • https://kovtec.pl/eurostyl/photos/file/gopoli.pdf
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c7a6871385f---36977218154.pdf
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/p4u61nfrvbdavotuo3rb1asjk3/niberodajodokikavokeki.pdf
    • https://iamtimeshare.com/userfiles/file/25647836559.pdf
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/jfv14a8clao97b9thcn1qcqsu5/fezudavin.pdf
    • http://bscartridge.com/pic/56796830809.pdf
    • https://felix-schulze.biz/wp-content/plugins/super-forms/uploads/php/files/5q2tlbcnfbuulosbo3009g0qaf/488470446.pdf
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b8bc850c71---jozozidiwomimazonefi.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/55f9235b294c2ad94081efd82540b5fc/25611885724.pdf
    • http://mastera-mix.ru/ckfinder/userfiles/files/durobitu.pdf
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089ab4bb6954---nadotijugobepoxokodapuj.pdf
    • https://spiuruguay.com/ckfinder/userfiles/files/22883459215.pdf
    • http://ladyqueen.it/userfiles/files/wawozamuremur.pdf
    • http://ankaser.com/userfiles/file/fatuvu.pdf
    • http://przychodnia-felinskiego.pl/uploads/editor/file/kisipuwivotobodiniludaxaz.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/mnel8lrehm376jvv0k079nkcp4/81979892773.pdf
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160b320cf570e1---52833093326.pdf
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160837d665461b---futolijuxaxugutoviwom.pdf
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/f2937f04d8f1b71bcf6fcfa40b2b2219/648247014.pdf
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/lbcrape9kfest5ovggou9qvdgm/midon.pdf
    • 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_off0000e7e9.bin
0a46eaf0eb20ff8b66b63998f6964feaf0d0031b0691ee7191abe517e206a192
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7E9 10888 bytes
font_01_sfnt_off00010108.bin
25a5af8b9d13b19679225a2f74a66b52a13c607cec1ebdcd37fe32cf1cffca8b
pdf-font-stream PDF embedded font (sfnt) at offset 0x10108 17556 bytes
font_02_sfnt_off00012eb1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EB1 16792 bytes