Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f7a6a03095c71df…

MALICIOUS

PDF

78.5 KB Created: 2021-09-02 01:37:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 690ed8420f8852da06e0fa7b6dd20a30 SHA-1: 39db7920c5efd95c6c798adbef9e0dc809d623b6 SHA-256: 8f7a6a03095c71df63a0ed941c1c07ac2c2d1f71b1ddd9f58c4f99aa810cd0e2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of PDF-specific heuristics like 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://pixomot.ru/uplcv?utm_term=miss+baker+the+great+gatsby
    • http://jr.ac.th/ckfinder/userfiles/files/25114228371.pdf
    • http://fantasymusic.it/userfiles/files/19441616004.pdf
    • http://world-spa-resorts.com/dok/37860295479.pdf
    • http://tvoirostov.ru/ckfinder/userfiles/files/9436906061.pdf
    • http://luatsugiadinhviet.com/upload/ck/files/67409028870.pdf
    • http://hykylalumni.org/userfiles/zisevuvopibeduxisefu.pdf
    • http://maxidmum.com/images/upload/fck/file/getiwakufaved.pdf
    • http://bestbuyfromindia.com/userfiles/file/44581518507.pdf
    • https://jjmassociates.com/wp-content/plugins/super-forms/uploads/php/files/d9a140c2706812df1c7c37701b0bc48d/57023777015.pdf
    • http://soles2walk.cz/data/file/53636648967.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/n7c6rsq1s8d7jrjadprq758mo2/86194744367.pdf
    • https://wineart.online/userfiles/file/51250670453.pdf
    • https://www.analfissur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072893dc70db---98113378552.pdf
    • http://amblesidewindermere.ca/fckuploads/images/file/zuzavufamivuwolatilixuwi.pdf
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160dca5d1b2296---48606362185.pdf
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160872d16da1d3---67561228049.pdf
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/7d50ee0087d78e310e122b30eaf25b9d/kagikuwaterubozun.pdf
    • http://whuntex.ru/userfiles/file/72157992712.pdf
    • http://homokkepek.hu/editor_up/rewavovavoxinesawodu.pdf
    • http://podiummoda.ru/userfiles/file/ruvurevezudakike.pdf
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ec424b4b80c---xinezak.pdf
    • http://skybuildinfraprojects.com/uploads/wajele.pdf
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/73d21b1e7df9260e1ae5744613aa9045/94644113014.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d026.bin
97c548f6cd8d0ec4003cc77fe9757ed4b3c78d99ecb2367aae05732b218de859
pdf-font-stream PDF embedded font (sfnt) at offset 0xD026 10456 bytes
font_01_sfnt_off0000e821.bin
782abae16c6da5289ff9a33591b9d3bba6051d5052413a397b967264a9990a12
pdf-font-stream PDF embedded font (sfnt) at offset 0xE821 17188 bytes
font_02_sfnt_off0001144e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1144E 16792 bytes