Malicious PDF — malware analysis report

Static analysis result for SHA-256 54affeba951bb7b8…

MALICIOUS

PDF

75.3 KB Created: 2021-09-13 12:51:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: 0cb34d60cbfd59e54bcbf4e5c5db5b10 SHA-1: f0ebac9bdc7444e4f8939289dbcdbe04b4849736 SHA-256: 54affeba951bb7b8a8837985c3f139e4b0f9663c92ec1b01a52199539557db53
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by multiple heuristics as malicious, including a machine learning classifier and ClamAV, indicating it is likely a phishing or trojan delivery mechanism. The presence of numerous external URIs, many pointing to disposable domains, suggests a link farm designed to redirect users to malicious content. Although no scripts were explicitly extracted, the PDF structure and the nature of the heuristics strongly suggest an attempt to exploit users through malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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 http://yomamasushitogo.com/uploads/files/mopokofaroferiberavof.pdf In PDF document text
    • http://citadelcaralarms.com/userfiles/file/kasugut.pdfIn PDF document text
    • http://lpxs168.com/filespath/files/20210901221430.pdfIn PDF document text
    • http://mazraeir.com/images/upload/files/gawoxepexawedoba.pdfIn PDF document text
    • http://www.valathors.com/ckfinder/userfiles/files/pasifikutovowamul.pdfIn PDF document text
    • https://parc-hotel.info/file/33718076748.pdfIn PDF document text
    • http://kaies.cn/upfiles/file/66117936935.pdfIn PDF document text
    • https://honkakuji.jp/honkakuji/images/ckfinder/files/59364247075.pdfIn PDF document text
    • https://imihwa.com/uploads/image/20210910/files/20210910081239.pdfIn PDF document text
    • https://songhong-thudo.com/img/files/zidobidavikowu.pdfIn PDF document text
    • https://cambodiadriverservice.com/userfiles/file/25379611727.pdfIn PDF document text
    • http://detaycopymatbaa.com/userfiles/file/kugejidumajikidegika.pdfIn PDF document text
    • http://childconnect.com/swi/fckfiles/file/20282829418.pdfIn PDF document text
    • https://vietucmould.com/img-vietuc/files/fedijofosawebaberu.pdfIn PDF document text
    • http://hemeringen.de/ckeditor_ablage/userfiles/files/3448384229.pdfIn PDF document text
    • http://tcihk.com/userfiles/36632626470.pdfIn PDF document text
    • https://simbhaolipower.com/images/file/xemuxu.pdfIn PDF document text
    • http://yingtailong.com/upload/file/210903121103054143d98cwchbz1zg.pdfIn PDF document text
    • https://yapluka-services.fr/userfiles/file/36197616498.pdfIn PDF document text
    • https://suma.ca/upload/editor/file/litijapeviw.pdfIn PDF document text
    • http://paneldeconso.com/userfiles/file/zivozoxag.pdfIn PDF document text
    • http://studiotecniconuti.it/userfiles/files/60096362771.pdfIn PDF document text
    • https://apc-algercentre.dz/ckfinder/userfiles/files/dunijobamogunolasibow.pdfIn PDF document text
    • http://xn--dlek-5qa.com/admin/UserFiles/file/69016328747.pdfIn PDF document text
    • http://theemasternetworker.com/ckfinder/userfiles/files/25537200468.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=samsung+s10+vs+iphone+11+proPDF link annotation
    • http://cluster006.ovh.net/~greeters/namur/ckfinder/userfiles/files/42116743849.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_off0000c229.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC229 16812 bytes
SHA-256: 772ad629a94c0e1f0221beaec1dad9c125a4d188a4c794d770745aaeb0216517
font_01_sfnt_off0000ed97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED97 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000105ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105AE 10972 bytes
SHA-256: 242acf7fd4f1e1e0ddbd2ddb5b45cfc467d59d21b6fd3aaddf1fdf6901c3f235