Malicious PDF — malware analysis report

Static analysis result for SHA-256 39840d384a9538af…

MALICIOUS

PDF

112.9 KB Created: 2021-07-02 07:06:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 28b52615a433edfb3bb3c0a6ec5ad742 SHA-1: 3b1e020592b7d3968301ba31f4b8f07e2cae68d1 SHA-256: 39840d384a9538af2a11e2352c1c44063e40dd62365a825a619e90b39e423dd4
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. No scripts were extracted, but the structure and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://agataklimowska.pl/userfiles/file/85931377301.pdf
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bdc32b2c69---90710248642.pdf
    • http://uptownchantilly.com/uploads/files/fakikofiduk.pdf
    • https://baohohoanglong.com/userfiles/file/86817963953.pdf
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/002929d63de0235cb60ee0af52342486/26341166158.pdf
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f0bc3004fc---52062156950.pdf
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a73b25bea01---buvumexadod.pdf
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/780b930b18100dd4e6d7135aa56629aa/24305637691.pdf
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/36ffc49f556ff258a168f3afd7fe0aff/55707754949.pdf
    • http://nsdadventist.org/FCKData/file/bizajekopobufebivesovev.pdf
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/8c0625d6567b77561a7eed056e6b2d1b/japafurofazexeligagapo.pdf
    • https://africanresearchcenter.com/userfiles/file/59902321636.pdf
    • http://sake2metustin.com/uploads/files/43556633498.pdf
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/97925090ee4614430eb470d8407ff403/wizorijudulekulutepikepef.pdf
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/pm9p8jqmupoq3gt13ntl4upqvl/62689215604.pdf
    • http://bjhtdszdh.com/v15/Upload/file/2021531543225702.pdf
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/jixosemonewakanofi.pdf
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d85be528ea---34098383364.pdf
    • https://lasvegasrebath.com/wp-content/plugins/super-forms/uploads/php/files/5504ae5ccb7d58b9a44263210f0b62b8/tavuk.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/2d67b324729b1ec265cd40f8f9b54b91/gujibopenorekuxezaru.pdf
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/2c8ef3ccff69bd6ee762dc72b8bba735/katukubiwex.pdf
    • http://vanharteyoga.nl/uploads/files/batuwadejikenidefijed.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=drop+table+tablename
    • 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_off0001585a.bin
3ec95f116a9d45a0c0ba975f41d60c6708421ac29be1aba4833999c4773f1bc8
pdf-font-stream PDF embedded font (sfnt) at offset 0x1585A 17312 bytes
font_01_sfnt_off000185da.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x185DA 16792 bytes
font_02_sfnt_off00019df1.bin
53862299515a97b54e66ab12927931174a8dc42581184fcb7fd8d199d57306d5
pdf-font-stream PDF embedded font (sfnt) at offset 0x19DF1 10292 bytes