Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef8617429962c33d…

MALICIOUS

PDF

86.4 KB Created: 2021-08-18 23:32:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-23
MD5: 08bba2828ca9064d5d1c78f200813a9e SHA-1: c05366900a3eaa84a0204c209cc95d72825daadf SHA-256: ef8617429962c33db3dd026a5af7627e9482c51035261d0217fda160eb1f6e16
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a security-bypass lure. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • Security software disable instruction high SE_SECURITY_BYPASS
    Document instructs the user to disable antivirus or security software — unusual for ordinary documents and high-risk in an unsolicited file
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://sanga.asia/userData/board/file/mamikodexutuvubis.pdf In PDF document text
    • http://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160714cfb0011b---57373689899.pdfIn PDF document text
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/1u0ms85ncbij9atsimj791de99/35138321570.pdfIn PDF document text
    • http://forter.vn/hinhanh/file/32238819876.pdfIn PDF document text
    • https://ottopianos.nl/files/koxokopaxupitazil.pdfIn PDF document text
    • https://noventa.cz/media/files/file/20952006995.pdfIn PDF document text
    • http://worthingtonpark101.com/userimages/nefederutipiso.pdfIn PDF document text
    • http://dj-venci.com/uploads/pages/files/dujomemakadur.pdfIn PDF document text
    • https://laser123.com/geektic/files/padawuladep.pdfIn PDF document text
    • http://clairerolo.com/userfiles/file/653052710.pdfIn PDF document text
    • http://studiolaviano.it/userfiles/files/95205235803.pdfIn PDF document text
    • http://gleneaglehoa.org/images/file/67991041160.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/60342516818.pdfIn PDF document text
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/078ca40734dccd0ced3d61b5572a2204/fofatufozamidebedeju.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4c8f931ef3---jafifoxukogavuriponogeb.pdfIn PDF document text
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/c4e3ff196876e1906f757ae8776f7d46/runexovazule.pdfIn PDF document text
    • http://videofilm-tv.ru/content/File/wufedovexelevebi.pdfIn PDF document text
    • http://fontanarosaserigrafia.it/userfiles/file/xunubi.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/5079ff9ec59908e8041b5895af1be53a/xapopagiven.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b33dfc96acc---34296940875.pdfIn PDF document text
    • http://3qbuy.com/CKEdit/upload/files/13751751304.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607df04a4abaa---fosoxegilowemuw.pdfIn PDF document text
    • https://mavachhaiphong.com/upload/files/60979874728.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=xilisoft+video+converter+ultimate+7+free+download+with+crackPDF 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_off0000e152.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE152 11144 bytes
SHA-256: cba9c4b9ef901ef5c9ebae1dc1cb35e82662d74fa4af24201f49282a2c06b881
font_01_sfnt_off0000fb41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB41 21340 bytes
SHA-256: 1465e383a2e80c9fc2910045161c8779895b6594206c2999278f30ffd3cc043a
font_02_sfnt_off0001307d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1307D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1