Malicious PDF — malware analysis report

Static analysis result for SHA-256 c21fc12734050151…

MALICIOUS

PDF

81.0 KB Created: 2021-09-20 02:31:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 367178bcc07d207fec5f0f7e894925d9 SHA-1: 346f1c86ac71c88bd94928884a12bde3574c9e27 SHA-256: c21fc1273405015190640cbac10b8d317fab1b077f90d8bd2c4e18590c1b96e9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting and are part of a link farm, indicating a phishing or malware distribution attempt. The presence of external URIs and the nature of the heuristics strongly suggest the document's purpose is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://irlanc.ru/uplcv?utm_term=how+to+switch+your+storage+to+sd+card PDF link annotation
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613b97afd0daf---gasajevododu.pdfIn PDF document text
    • http://tradotel-riviera.com/file/2053807519.pdfIn PDF document text
    • http://agnieszkapawlik.com/userfiles/file/34847352155.pdfIn PDF document text
    • http://reclameindex.nl/images/uploads/buzalam.pdfIn PDF document text
    • http://emotionpicturesfestival.gr/userfiles/file/68849003979.pdfIn PDF document text
    • https://akapacha.com/userfiles/file/52357844576.pdfIn PDF document text
    • https://drivetripper.com/userfiles2020/files/92083185450.pdfIn PDF document text
    • http://ceramicaartisticamarsalese.it/userfiles/files/bubewaxopolat.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/8a163125d15a64c4f5f9d0802d2aa321/jewajerelatotaxiluwoli.pdfIn PDF document text
    • https://demo.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/22964627306.pdfIn PDF document text
    • http://creationart.hu/files/file/kozasukizen.pdfIn PDF document text
    • http://rubivina.com/Images_upload/files/13339853787.pdfIn PDF document text
    • https://ce-mi.pl/uploads/userfiles/files/jagasixivaxeb.pdfIn PDF document text
    • http://eptesteplelek.com/uploads/file/5976371175.pdfIn PDF document text
    • http://wagnerpc.com/userfiles/files/pudemaxevetenak.pdfIn PDF document text
    • http://ih-consultant.com/ckfinder/userfiles/files/dugitarozijazipopul.pdfIn PDF document text
    • http://tpfish.com.taipei/archive/upload/files/87484871425.pdfIn PDF document text
    • http://bkmarine.net/ckfinder/userfiles/files/1630492358.pdfIn PDF document text
    • http://bakefruit.com/uploads/files/202109080021273866.pdfIn PDF document text
    • http://tongchangkj.com/uploadfile/file///2021091209255672.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/38360698686.pdfIn PDF document text
    • http://ckm-machinery.com/userfiles/files/mazuzoletaxobutekunozen.pdfIn PDF document text
    • http://flexinform.com/hirlevel/file/78339533574.pdfIn PDF document text
    • https://eldorado777.ro/upload/editor/file/10951515945.pdfIn PDF document text
    • 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_off0000d33c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD33C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eb4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB4E 19488 bytes
SHA-256: 4af0ce97fcbee8752e7df60d7172b8195c9b16ff85f77c5df7635a0259af2ae2
font_02_sfnt_off00011db0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DB0 10788 bytes
SHA-256: 0059498d20f47d3095ee40c04fffc2338b45d147c775c9d07d4dc70ac2e42744