Malicious PDF — malware analysis report

Static analysis result for SHA-256 358b03c45039ec39…

MALICIOUS

PDF

75.9 KB Created: 2021-09-18 20:59:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1948420461e0d29bdf20a0d207ebf234 SHA-1: 32e7519cacf245c5ad07ee24c4ad3bfbfdc67223 SHA-256: 358b03c45039ec39a0782560659ef42fd2df22c73c7daa6dfb6ebb28e4e27eed
96 Risk Score

Malware Insights

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

The PDF was flagged by an ML classifier as malicious with high confidence. Heuristics indicate it functions as a link farm, with multiple URLs pointing to compromised WordPress upload directories, suggesting an attempt to host or distribute further malicious content. The presence of these links and the overall structure strongly suggest a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • 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://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131382fc8aa2---buvatorusudawefevowiruxu.pdf In PDF document text
    • https://zilalcooling.com/other_files/File/nimilolisula.pdfIn PDF document text
    • https://www.studiorosaliabusco.it/ckfinder/userfiles/files/munuled.pdfIn PDF document text
    • http://ctnphrae.com/ckfinder/userfiles/files/89931461268.pdfIn PDF document text
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/77248133629.pdfIn PDF document text
    • http://xn--80akoseq9f.xn--p1ai/userfiles/file/82766950321.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161451bcf0f565---48662318737.pdfIn PDF document text
    • http://nenorm.com/files/files/49098684053.pdfIn PDF document text
    • https://yesilkoyluleriz.biz/resimler/files/xuganuvulugusutisabekod.pdfIn PDF document text
    • http://tincorner.vn/uploads/files/muwikiwisorexazagu.pdfIn PDF document text
    • https://adrfarysz.pl/userfiles/file/55364273551.pdfIn PDF document text
    • http://fcraregistration.com/UploadedData/file/penikeza.pdfIn PDF document text
    • https://binarbaidrealestate.com/public_html/userfiles/file/82772684131.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/janezivinowutuworetos.pdfIn PDF document text
    • http://sergeisurzhin.ru/ckfinder/userfiles/files/44896312638.pdfIn PDF document text
    • https://alperbehang.nl/userfiles/file/44219697413.pdfIn PDF document text
    • https://www.lsv-wittlage.de/ckfinder/userfiles/files/kewesi.pdfIn PDF document text
    • https://yarpaket.ru/userfiles/file/zozurura.pdfIn PDF document text
    • http://chikatere.com/Upload/files/lipiludikukituvulejaf.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/161429a7e2707a---38071246843.pdfIn PDF document text
    • http://ratchadatitan.com/UserFiles/File/xolenerumopuxuzavar.pdfIn PDF document text
    • http://sutipatika.hu/userfiles/files/setatudazofar.pdfIn PDF document text
    • http://net-marketing.hu/images/files/52082132066.pdfIn PDF document text
    • http://elard-group.com/ckfinder/userfiles/files/42177530771.pdfIn PDF document text
    • http://trunglam.vn/uploads/userfiles/file/ralexexixuni.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=forum+hack+wifiPDF 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_off0000c835.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC835 16684 bytes
SHA-256: ffdc03bc562d48d91fb27e5f8d20f19814f8f2f99c59f1415880670e5f46713c
font_01_sfnt_off0000f33e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF33E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B55 10308 bytes
SHA-256: dd7de96ff5c29fbdb34948c3e70618b03f6ab101875dd04ae29d51b0190f50a7