Malicious PDF — malware analysis report

Static analysis result for SHA-256 800c274cd61def32…

MALICIOUS

PDF

69.0 KB Created: 2021-09-25 10:19:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 93bfacccda67b1e481544cb6debdc0db SHA-1: a8e908c6a165da32d75e48aecde37945313c53f1 SHA-256: 800c274cd61def322964709cdc69d6dc8cb76e6d8500f26bcfb729b57e5fc9e3
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by multiple heuristics as malicious, including a link to an algorithmically generated URL and detection as a phishing trojan by ClamAV. The document body is heavily obfuscated, but the presence of external URIs and the overall structure suggest it is designed to redirect users to other malicious content. The ML classifier output of 0.998621 further supports the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://xn--bren-mgenwil-gcbf.ch/sites/default/files/fck-uploads/file/jogadesovawigetun.pdf In PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d8747c40c1---situgomuxajetugimaw.pdfIn PDF document text
    • http://avatars.ru/userfiles/file/60920777720.pdfIn PDF document text
    • http://location-venise.com/italie_documents/files/16829921849.pdfIn PDF document text
    • http://imdmotors.com/uploadfile/file/2021090612471443.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134af7e3bf3f---detiripababuwesinaruk.pdfIn PDF document text
    • http://cybernet-ap.com/UserFiles/File/gerolitivuzaromuve.pdfIn PDF document text
    • https://anglarill.net/userfiles/file/19705913207.pdfIn PDF document text
    • http://fiumevivo.it/userfiles/files/10988378264.pdfIn PDF document text
    • http://bajajsports.com/userfiles/file/83672409339.pdfIn PDF document text
    • http://orbitsecurity.qa/pro_mvp_tech/uploads/file/jawibakofesadibulefimazu.pdfIn PDF document text
    • http://surveycook.com/upload/tmp/202109/file/75960003041.pdfIn PDF document text
    • http://e-park.es/img/uploads/files/raxabopakoziwikivoz.pdfIn PDF document text
    • https://b2bircruise.travflex.com/bot/ckfinder/uf/files/95127129668.pdfIn PDF document text
    • https://brtim.com/uploads/wysiwyg/files/74807580176.pdfIn PDF document text
    • http://turinimoti.com/assets/userfiles/file/54860142318.pdfIn PDF document text
    • http://veterinarioassociatopacinidallatorre.eu/userfiles/files/kosepiveduloli.pdfIn PDF document text
    • http://0985028898.kad.tw/kads/ckfinder/userfiles/files/nixuxetekunipade.pdfIn PDF document text
    • http://exima.kr/userData/board/file/doxidabuxasake.pdfIn PDF document text
    • https://dukupahit.com/contents/files/30305918831.pdfIn PDF document text
    • http://andreuma.madteam.net/ckfinder/userfiles/files/1533043844.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=heroes+of+dragon+age+mod+apkPDF 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_off0000af14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF14 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c726.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC726 15376 bytes
SHA-256: b4f377c9c285d5ff83a13b8874d5871e316d3fa356241a61960585a7613b9dbe
font_02_sfnt_off0000ee22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE22 10688 bytes
SHA-256: c44ec9a3b103d8045fd67f735716b1ce903fb778f07a800e87435fb71187f2fb