Malicious PDF — malware analysis report

Static analysis result for SHA-256 de7e20ae68bbcfac…

MALICIOUS

PDF

84.4 KB Created: 2021-09-23 09:43:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f51e836716a6302a1dca048ad09db84c SHA-1: 8abc078cec9dc211b93ca3d1eecbf72992158f4b SHA-256: de7e20ae68bbcfac6868a324bda9560b6b99b653cb3dd0b6d5aa3012757535dc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised WordPress upload directories, suggesting a link farm designed to host malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a spearphishing attachment used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9075a1ab0---8118670111.pdf In PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/ca7d6992d9b5d9be56acfec306897af2/96417504601.pdfIn PDF document text
    • http://xn--aknmedical-yub.com/uploads/file/58655894880.pdfIn PDF document text
    • https://plasy.com/uploads/file/rarusafubef.pdfIn PDF document text
    • http://www.sindafaz.com.br/admin/editor/ckfinder/userfiles/files/fitigivumokobuxalefi.pdfIn PDF document text
    • http://oipipleszno.pl/userfiles/file/71799709920.pdfIn PDF document text
    • http://stoewebdesign.no/userfiles/file/rekamujekajuz.pdfIn PDF document text
    • https://chinese-wall.tw/upload/files/kelenabi.pdfIn PDF document text
    • http://yusungchart.com/userData/board/file/58442242144.pdfIn PDF document text
    • http://generale-bureautique.fr/gdb/files/file/42806380867.pdfIn PDF document text
    • http://ros-grad.ru/fck_editor_files/files/2994780491.pdfIn PDF document text
    • https://sanaspinler.net/calisma2/files/uploads/gadoro.pdfIn PDF document text
    • http://thaisomboonautopart.com/userfiles/files/silafi.pdfIn PDF document text
    • https://centaur.vri.cz/docs/files/53064761211.pdfIn PDF document text
    • http://bbdecontra.com/userfiles/files/takusopulozewagasu.pdfIn PDF document text
    • http://heibldr.hu/FCKfeltoltott/file/roboxevaf.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140c3e281b23---6790885937.pdfIn PDF document text
    • https://z87992961.com/upload/files/20210908064556.pdfIn PDF document text
    • http://slkuang.com/v15/Upload/file/20219434599683.pdfIn PDF document text
    • http://fsgpj.com/upfolder/e/files/20210923085731.pdfIn PDF document text
    • http://k-sta.kr/FileData/ckfinder/files/20210921_E657AC249A14B436.pdfIn PDF document text
    • https://websbag.com/uploads/files/lovifif.pdfIn PDF document text
    • http://simoncaulkin.com/images/15299776105.pdfIn PDF document text
    • http://meadescafe.com/userfiles/file/9597041209.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f9b9101fbe---9445079592.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=amplitude+and+period+of+a+sine+functionPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e16f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE16F 10864 bytes
SHA-256: 6c2de40894e064787ed56fedb450bd6315b5067d2d03ce472765ef1fd95d0c3c
font_01_sfnt_off0000fa88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA88 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001129a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1129A 18640 bytes
SHA-256: a2b6e5bb6f7dd189cba183d792bd23015d5ed8aab2bc2f627df50044c730804f