Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3140f53a3f96253…

MALICIOUS

PDF

72.8 KB Created: 2021-06-21 08:08:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 4a1ad449ea85693ce7b8897e3f80c850 SHA-1: 5591125956630bef9db5e0c35125de804d942af2 SHA-256: f3140f53a3f96253f6deec6efa88f8584a9783c24fae1418f3f57b0171c25096
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised WordPress upload directories, suggesting an attempt to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues to its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f282daeae5---23713287547.pdf In PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/uvi8hifp9hjqni9c19qqsdbj0c/7019892819.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160800386092b6---sugojowuvodebetoruraz.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7ae13a6c45---keteboxunoribus.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/0uu2c6sf1getnkgveq7d6499li/80169333463.pdfIn PDF document text
    • https://novahealthclinic.ca/userfiles/file/wezunotovi.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a9c1c1ac367---minevevijoselogat.pdfIn PDF document text
    • http://amandamaitland.com/images/file/sonalosojavadotosuzoge.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/e83l7ftuub3nb29hum3vvs0hr3/11283548116.pdfIn PDF document text
    • http://tea-ra.com/user_data/upload/save_image/files/64078281746.pdfIn PDF document text
    • http://cherishedmomentphotos.com/clients/8/84/84fe84b553acfcd191e166b7401b6f02/File/78698375824.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/ksf56cdk241bvtu0frslsdml16/vaxudodufug.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/e3db5db8724af5fec05947c3ffc61c39/63648786013.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/5c2614271c0724feb83de6d6b4b78f95/40323495913.pdfIn PDF document text
    • https://angelsforwarriors.org/userfiles/files/xilajizukorovewifirurunan.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/ce9eecb52d3ad055b8533cbd051798c3/fagizitekedilebexaka.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16071ad2e6e14e---vuvijis.pdfIn PDF document text
    • http://grodgolf.com/clients/f/fd/fd83fa7079552abb47853a85229f74c1/File/rowatadobafi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=vermintide+2+traitsPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dd71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD71 5036 bytes
SHA-256: d11c27faf9fd5e73d72668cd0570f7978838fc30584fc689deaade84cedd1dee
font_01_sfnt_off0000ee7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE7B 11720 bytes
SHA-256: 756e40c55306dbb21df72fe8cdd0f1c37eb6cb5e4fc5672454c996afb1b17a5b