Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc983e079726ca19…

MALICIOUS

PDF

79.5 KB Created: 2021-09-19 12:20:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f7b946325b29dc5b6ab9374170f7b659 SHA-1: a9cfd32300a758c2554dcee3172ee85b67d0ad84 SHA-256: fc983e079726ca1958cec1d61e85405683bb488d2d82cac0be526f69bdf01cdc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to various domains, many of which appear to be part of link farms designed to obscure the final malicious destination. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, further suggesting a malicious intent to distribute or phish.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://crewmak.ru/uplcv?utm_term=unturned+id+suppressor PDF link annotation
    • http://shinex-auto.com/userfiles/file/wuzajejewadule.pdfIn PDF document text
    • https://lexcyberia.com/userfiles/files/98868478795.pdfIn PDF document text
    • https://brihat-group.com/assets/userfiles/files/96363551146.pdfIn PDF document text
    • https://derechosenred.org/aym_image/files/62368047065.pdfIn PDF document text
    • http://nwhouse.ru/uploads/file/18180454006.pdfIn PDF document text
    • https://99shayari.in/userfiles/files/votoj.pdfIn PDF document text
    • http://studioturina.com/userfiles/files/febofu.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16145e88e8a1ec---9804342231.pdfIn PDF document text
    • http://www.specemc.ru/upload/files/lezuxudozaxijadi.pdfIn PDF document text
    • http://urparitet.ru/admin/ckfinder/userfiles/files/vobozepogenenolulofopuw.pdfIn PDF document text
    • http://www.lebedosapartotel.com/data/yukle/files/23122080994.pdfIn PDF document text
    • http://wuyioutdoor.com/userfiles/file/paxasenuzub.pdfIn PDF document text
    • http://gr-chem.com/upload/files/2480821323.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/8791023b71f1b7bcc5fec77f6fa00659/80686434874.pdfIn PDF document text
    • http://gradn.ru/uploades/fckeditorfile/tiwejisirezuvib.pdfIn PDF document text
    • http://cgmorenanews.com.br/ckfinder/userfiles/files/jizenisupuradiwigemed.pdfIn PDF document text
    • https://xuanhongkhang.com/upload/files/rikotipudosidolimom.pdfIn PDF document text
    • https://dogodanang.vn/uploads/image/files/pogavovosofip.pdfIn PDF document text
    • http://www.pes.edu.mn/ckfinder/userfiles/files/8926953397.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/gdla937a7qma4e4s6jk3evp0vi/14516405018.pdfIn PDF document text
    • https://muahohangnhat.com/app/webroot/uploads/files/53144355306.pdfIn PDF document text
    • http://ivankotov.ru/img/lib/file/zeguposo.pdfIn PDF document text
    • https://idea-web.ro/app/webroot/files/userfiles/files/72865456458.pdfIn PDF document text
    • http://tabbanbros.com/admin/fckeditor/editor/filemanager/connectors/upload/file/50178893646.pdfIn PDF document text
    • https://onlineadda.net/ckfinder/userfiles/files/renonexagezetotekelik.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_off0000d3cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3CF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ebe6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBE6 10284 bytes
SHA-256: bca85095e9077271ccd681dbc9dbd6a462bcd9dfa1323f84ac961f44660448a0
font_02_sfnt_off00010321.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10321 17508 bytes
SHA-256: f8f1facb6f40a402cdcd1944cb52180942c553a3a9270972935282916c10ac58