Malicious PDF — malware analysis report

Static analysis result for SHA-256 2d5b3fb9f42116e5…

MALICIOUS

PDF

82.3 KB Created: 2021-09-12 15:45:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 60cf58193ccdad7456e2f54d2ec7c4aa SHA-1: d585bb3bed12e0b4acd5ad8784e0c4d1fabf4021 SHA-256: 2d5b3fb9f42116e5dd6a9cf73b208cdc0a0a9979f94eb4cfd489ecaf79f3fbfb
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to other PDF files on various domains, indicating a link farm. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic and the high number of distinct hosts strongly suggest a malicious intent, likely for phishing or distributing further malware. The ML classifier and ClamAV detection further support its malicious nature.

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://rpsbchamber.org/editorData/file/wujejorem.pdf In PDF document text
    • http://exima.kr/userData/board/file/4711789946.pdfIn PDF document text
    • https://hsse.hssanesteban.cl/files/68000209678.pdfIn PDF document text
    • http://bluebiz.kr/userData/board/file/58731109818.pdfIn PDF document text
    • http://truhlarstvi-strakonice.cz/files/file/ralepelemifafegok.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/temeramulavekozerusetadu.pdfIn PDF document text
    • http://ekopaczka.pl/imgbrama/files/33966968363.pdfIn PDF document text
    • http://aurora-c.jp/files/files/92739756338.pdfIn PDF document text
    • https://kar360.com/resimler/files/fesowagafobelelipido.pdfIn PDF document text
    • https://mytopics.it/uploads/file/31697679798.pdfIn PDF document text
    • https://kurek-rowery.pl/user_pict/file/9663446884.pdfIn PDF document text
    • http://knowleangling.co.uk/ckfinder/userfiles/files/podozuwaxomizux.pdfIn PDF document text
    • http://xn--80aesyq.xn--p1acf/files/file/nelenugelej.pdfIn PDF document text
    • https://mchs.kz/userfiles/File/mukerosilemokatugapizu.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/c82db3f12f13b0104a2a92956e6c551f/busimujumajijasanulof.pdfIn PDF document text
    • http://aitrans.cn/UploadFile/file/F1202109120625165496.pdfIn PDF document text
    • http://99hospitalitygroup.com/ckfinder/userfiles/files/59584221943.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139bf9d96be2---xulalerimovepeputufajiw.pdfIn PDF document text
    • http://tpokebar.com/uploads/files/66796060709.pdfIn PDF document text
    • https://aitalk.vn/upload/files/gefawododafiz.pdfIn PDF document text
    • http://inoxbienhoa.com/upload/files/nitufusor.pdfIn PDF document text
    • http://posicert.com/upload_fck/file/2021-9-7/20210907120038725563.pdfIn PDF document text
    • http://ventilatoryzlin.cz/images/file/15515586257.pdfIn PDF document text
    • http://geometrarontani.it/userfiles/files/musatakevugulikuzedololaz.pdfIn PDF document text
    • http://vedepcuaem.com/luutru/files/paboxomugodotol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=steel+and+flesh+unlimited+moneyPDF 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_off0000dd16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD16 17744 bytes
SHA-256: a13b8cfe5c76b30fa8685db550e33e0643d2e68dcbd63a20af0f323fbe943d23
font_01_sfnt_off00010afa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AFA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012311.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12311 10808 bytes
SHA-256: d71933605f7bd625c2f22f895992e2d8b22d11cb9751270173aeb018e1851048