Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc1b38e2d5577d71…

MALICIOUS

PDF

82.7 KB Created: 2021-09-13 11:07:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5157cf11af220949c23a37086bf1b6ca SHA-1: 60ee79234c46c59f9b49707a0ad3976c032ba6f7 SHA-256: fc1b38e2d5577d716fc6b81974b7b974c369f21e5e2b51b60a85cc23e013f106
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many pointing to disposable hosting or compromised CMS uploads, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://chinese-wall.tw/upload/files/37811407147.pdf
    • http://emekyesiltepe.net/images_upload/files/50451860593.pdf
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bd12aa4b7f---61195415955.pdf
    • https://www.edm-medical.net/ckfinder/userfiles/files/42263716199.pdf
    • https://gifarlcm.com/upfiles/editor/files/pojevuxubibojafuvefavef.pdf
    • https://il-gusto.com/images/file/25736158237.pdf
    • http://haai.org/upload/file/buzanumopalij.pdf
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/7d80176e3999cf205749852127b0248e/rujeve.pdf
    • http://fusen-es.info/yamituki-n/uploads/files/76597859514.pdf
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139ab8d191b8---jetenusewujar.pdf
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/8b440ae209a6f2cdc6517fb09d5b562d/pigupukisuxedibaparap.pdf
    • https://aaaxxion.info/images/file/95030017958.pdf
    • http://yachtandgulet.com/userfiles/file/40729037660.pdf
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b9cc63cdd3---85239579338.pdf
    • http://printrun.nl/userfiles/files/55832747305.pdf
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/9dd83f8b1b1838faa8ef19e36bc37b24/kizodufafagotipugeg.pdf
    • https://taxforce.nl/userfiles/files/12077818249.pdf
    • http://lightningriskassessment.com/ci/userfiles/files/46935697941.pdf
    • https://www.barefoothoa.com/webroot/js/ckfinder/userfiles/files/wenakanilebekopo.pdf
    • https://ferado.vn/userfiles/file/4115589107.pdf
    • http://cesishotel.com/res/wysiwyg/file/33671302283.pdf
    • https://xtremefitksa.com/ckfinder/userfiles/files/43629244469.pdf
    • http://www.biosafety.biz/ckfinder/userfiles/files/84921831437.pdf
    • https://garnizone.com/userfiles/file/40238553207.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+remove+built+in+apps+android
    • 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_off0000dcc1.bin
fdd6cec2cd7036cc98b079c0e985c63e373901594a89e77f31fb809b7a626122
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCC1 10936 bytes
font_01_sfnt_off0000f5dc.bin
cd4e472ecf5c7c23077ea7658911334adb20b8bcf01d090144861df53c5b4d5a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5DC 18456 bytes
font_02_sfnt_off0001252f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1252F 16792 bytes