Malicious PDF — malware analysis report

Static analysis result for SHA-256 10689815b5bb1cc8…

MALICIOUS

PDF

83.1 KB Created: 2021-09-18 06:11:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 1e5b8c288bcb13bfa37333b3a65f5fad SHA-1: e637b7c66563c7ea0822cc7b87625361614aab07 SHA-256: 10689815b5bb1cc8d07cdf03d4512ad1e3d13a991a2f59c3c8c91cf712bbf27f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous external URIs, many of which point to disposable hosting, suggesting a link farm or phishing operation. The presence of embedded URLs and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly indicate that the PDF's primary purpose is to redirect users to malicious websites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://ketchas.ru/uplcv?utm_term=top+10+audio+player+for+android PDF link annotation
    • https://ltes2.tw-goods.com/UserFiles/files/nidevamosoguvagewupijuluf.pdfIn PDF document text
    • http://cpgny.com/userfiles/files/48787383600.pdfIn PDF document text
    • http://eastindiaspray.com/suvra/eastindia_spray/files/sodininosigitabojimunozuw.pdfIn PDF document text
    • https://fanaf.org/article_ressources/file/87359689387.pdfIn PDF document text
    • http://longarmacademy.net/fckeditor/userfiles/file/godifabiw.pdfIn PDF document text
    • https://solturism.ro/images/file/xikatemenanudokusag.pdfIn PDF document text
    • https://bitree.ru/ckfinder/userfiles/files/tawilumosomezi.pdfIn PDF document text
    • http://astprom.ru/sites/default/files/file/fetudezojodefudofogoki.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133dabb71edd---todulokonutigevomozulelag.pdfIn PDF document text
    • http://elai.kz/upload/2021/09files/21090201535591321572yi3.pdfIn PDF document text
    • http://zehanbiopharma.com/upload/files/webigipomot.pdfIn PDF document text
    • https://inprovitcolombia.com/ckfinder/userfiles/files/51980472428.pdfIn PDF document text
    • http://myphamlulanjina.com/upload/files/94977711357.pdfIn PDF document text
    • http://enotecagaribaldi.it/userfiles/files/zamuromabamiki.pdfIn PDF document text
    • https://035620126.tw/upload/greenkitchen/files/6201735983.pdfIn PDF document text
    • https://hotararicedo.ro/files/files/fonuwafenum.pdfIn PDF document text
    • https://beta.nhatthiengroup.com/files/uploaded/files/6889418107.pdfIn PDF document text
    • http://saddabro.com/userfiles/file/91434531539.pdfIn PDF document text
    • http://siamsnail.com/media/userfiles/files/74029710184.pdfIn PDF document text
    • http://anadolumatbaa42.com/genelresimler/file/31759361567.pdfIn PDF document text
    • https://ckv-siemreap.org/ckfinder/userfiles/files/89844839447.pdfIn PDF document text
    • https://babetravelling.com/ckfinder/userfiles2/files/32448601731.pdfIn PDF document text
    • http://cy2hand.com/userfiles/73034196239.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613113a738f64---ripinijidoki.pdfIn PDF document text
    • https://economiadecomunion.com/ckfinder/userfiles/files/79055717653.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_off0000e134.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE134 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f94b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF94B 10576 bytes
SHA-256: 101fa2e5efb074775abea3576741b633bec7f5b421b52140119ee08337d4d5e6
font_02_sfnt_off0001117a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1117A 17244 bytes
SHA-256: 9f299017b202b4baa158d2ae282de680074ca6ae349f4886dcbbf14afe6f8068