Malicious PDF — malware analysis report

Static analysis result for SHA-256 52dabce623eda5a5…

MALICIOUS

PDF

70.2 KB Created: 2021-10-04 10:50:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 54c061d049b1ae33562f3e85b859a630 SHA-1: 2936579c5ab9eef35011c90808ebeb75b94250d9 SHA-256: 52dabce623eda5a5c8c5fc53f3281bf70ed75dd806b74e40281c12e337a6ed12
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV detection, indicating malicious intent. The presence of numerous embedded URLs, many pointing to disposable domains and structured as a link farm, suggests a phishing or malware distribution scheme. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure points to the exploitation of user trust to redirect them to potentially harmful external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://oreoltour.ru/sites/default/files/file/37010825173.pdf In PDF document text
    • https://paeonia.ch/userfiles/files/20153862892.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/161373503c97f9---xegozon.pdfIn PDF document text
    • http://rjbmachinery.com/d/files/mevezoxovekesuxak.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-9-4/20210904142739782264.pdfIn PDF document text
    • http://hbisan.com/userfiles/file/kanobupedapavuzuk.pdfIn PDF document text
    • http://sarkar.ie/userfiles/file/pozerufusig.pdfIn PDF document text
    • http://gibisch.info/files/files/movijepexinal.pdfIn PDF document text
    • http://cornaredo.gattinonimondodivacanze.it/themes/userfiles/files/safakevorujojidojaj.pdfIn PDF document text
    • http://slovoveri.org/userfiles/tabonitosezaxufolowuga.pdfIn PDF document text
    • http://pradakshinam.com/fck_uploads/file/64640243596.pdfIn PDF document text
    • https://shoppingplanet.cityplanet.ro/ckfinder/userfiles/files/48481264832.pdfIn PDF document text
    • http://textstricker.de/benutzerdateien/rosigope.pdfIn PDF document text
    • http://swaving-stalinrichting.nl/ckfinder/userfiles/files/gawamozugufoge.pdfIn PDF document text
    • http://vitacanes.com/uploads/files/9614893906.pdfIn PDF document text
    • https://dolupin.com/calisma2/files/uploads/natixozisobowivekurej.pdfIn PDF document text
    • https://autotronics.vn/userfiles/file/xaxik.pdfIn PDF document text
    • http://airsoft1.ro/files/file/zevavetiforuf.pdfIn PDF document text
    • http://lidaoxc.com/upload/files/lijolanavigideso.pdfIn PDF document text
    • https://bienenaktuell.com/sites/bienenaktuell.com/files/file/gefoweku.pdfIn PDF document text
    • http://gz-theoutfit.com/UploadFiles/FCKeditor/20210909001503.pdfIn PDF document text
    • https://foundryindia.org/userfiles/file/fatusokozijejibiputosemoj.pdfIn PDF document text
    • http://vinaktv.com/storage/ckfinder/files/44787334248.pdfIn PDF document text
    • https://www.hmgfinance.com/ckfinder/userfiles/files/jezobizenivuditejezegob.pdfIn PDF document text
    • http://fkjz.cn/upload/files/2021/09/202109200307318113.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=is+there+a+way+to+see+a+private+instagram+accountPDF 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_off0000af92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF92 11092 bytes
SHA-256: c1358d15185a914f1c99b7a1da58b4ab581e884652975ca2b3b65692cd7008ab
font_01_sfnt_off0000c96a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC96A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e17c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE17C 15664 bytes
SHA-256: a3e0f0165d1d3dedfe7a9a5cd88dee955d851ba3043d90f47d9cc73d0828b297