Malicious PDF — malware analysis report

Static analysis result for SHA-256 c31f901553747ff1…

MALICIOUS

PDF

77.6 KB Created: 2021-10-05 10:47:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d34ae8ff2a3c94de4af4d6102c884764 SHA-1: c695506a095d53151243649db0cc2a79e328f5a7 SHA-256: c31f901553747ff182e528711fa944f6883a13d321263a044105b9f69259a87f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by multiple heuristics, including ClamAV and an ML classifier, indicating malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it functions as a link farm, directing users to numerous distinct hosts. The embedded URL `https://oniceh.ru/uplcv?utm_term=how+to+see+posts+of+private+instagram+account` indicates a potential phishing lure related to social media privacy.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://oniceh.ru/uplcv?utm_term=how+to+see+posts+of+private+instagram+account PDF link annotation
    • http://electrogalicia.com/electrogalicia/recursos/archivos/24530349039.pdfIn PDF document text
    • http://planet-for-events.de/userfiles/file/91467813562.pdfIn PDF document text
    • http://summitremodelinginc.com/userfiles/files/tolikizuzuvazozasiteted.pdfIn PDF document text
    • http://okeefesreef.com/ckfinder/userfiles/files/nosomijawagifew.pdfIn PDF document text
    • http://www.brickchamber.com/ckfinder/userfiles/files/67079045985.pdfIn PDF document text
    • https://contact-house.com/fckeditor/upload/file/17009322637.pdfIn PDF document text
    • http://wisdomtours.net/upload/file/sewikuxijenijosefulip.pdfIn PDF document text
    • http://kondicionery-pushkino.ru/upload_picture/file/wozexejob.pdfIn PDF document text
    • http://gallery4walls.com/upload/editer/file/gitubasero.pdfIn PDF document text
    • http://3bbb.fr/ckeditor/upload/files/94086044378.pdfIn PDF document text
    • http://directartdeal.com/uploaded_files/userfiles/files/12071156416.pdfIn PDF document text
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/01ce6f9b4274d7fe87758a3a45ecb7cf/gerapotugefakixelopexef.pdfIn PDF document text
    • https://www.thaiahpa.com/flash/files/devibevetewomomezug.pdfIn PDF document text
    • http://k3projekt.pl/uploads/userfiles/files/99639247482.pdfIn PDF document text
    • https://alexandrapanayotou.com/web/images/static/file/58639286086.pdfIn PDF document text
    • http://pusheng168.com/uploadfiles/20210909134728.pdfIn PDF document text
    • https://gentrilieu.vn/userfiles/file/53280382518.pdfIn PDF document text
    • https://mpressivelabels.com.au/application/third_party/ckfinder/userfiles/files/raxojolemenemukipekuj.pdfIn PDF document text
    • https://santechnikosdarbai.lt/images/files/6565130230.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614f99a9ae2a7---kagawadijubuwefof.pdfIn PDF document text
    • http://winso.tw/userfiles/file/puxuto.pdfIn PDF document text
    • http://scard.vn/app/webroot/uploads/files/18668192904.pdfIn PDF document text
    • http://telegid.tv/userfiles/files/navisofa.pdfIn PDF document text
    • https://floridahouselottery.com/test/userfiles/file/zolajuzotok.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/12523638751.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_off0000cb3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB3B 11020 bytes
SHA-256: 33b42b9363bf53278b9bcef65b032943253bcd308d17bd000cd166097aebab79
font_01_sfnt_off0000e4ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4ED 16756 bytes
SHA-256: 57fe9e4626463abd4fe752135a990ea7adb576552f16b0f93a3efad67c5258ae
font_02_sfnt_off0001100f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1100F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1