Malicious PDF — malware analysis report

Static analysis result for SHA-256 0b40df132f254957…

MALICIOUS

PDF

82.5 KB Created: 2021-09-13 06:54:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4c429f183d4f4a6cb3e11c54c4ec5177 SHA-1: 820f12b0df59957b2d15e4497bf48b5c26486815 SHA-256: 0b40df132f254957829d060102ff5a7786e7052ce06d53d7e831a5868d89fd42
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. The sample also exhibits characteristics of a link farm, with numerous URLs pointing to potentially compromised or disposable hosting, suggesting an attempt to obscure the final malicious destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • 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.
  • 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 http://danguykhoidoanhnghiephp.vn/Upload/files/sanowanepuwepixarilex.pdf
    • https://ssmavidiyar.com/public/content-images/files/madulixat.pdf
    • http://shiokuda1.com/contents/files/8202915664.pdf
    • https://suadienlanhhanoi.net/upload/files/34130553883.pdf
    • https://olterus.com/contents/files/zuvijez.pdf
    • https://baatco.com/ckfinder/userfiles/files/jetarubu.pdf
    • http://torgoborud.org/images/file/73860422361.pdf
    • http://www.leads-bd.org/app/webroot/js/ckfinder/userfiles/files/dorakepadisoposuminu.pdf
    • http://vhktn.at/images/content/files/simawerurenerimixafamas.pdf
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/b7a9fdcc166a99fe69210bb149c9f8e9/44024783299.pdf
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/1fb75ba8e95cf4b37b3a5c0c5513aa60/51885254456.pdf
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613559567fa28---xizapudedekudibunero.pdf
    • https://auto826.com/uploads/files/21794235885.pdf
    • https://whitesal.com/data/images/file/4909_20210911184658.pdf
    • http://garmaclima.com/uploads/ckfinder/files/99702483000.pdf
    • https://adetexfoamgroup.centralcms.cloud/galeria/files/golodesimufapufamuxigon.pdf
    • https://asken.as/bilder/file/meloxodawumabewizoregojop.pdf
    • https://catequesisnavarra.org/guiarte_userfiles/files/94975754505.pdf
    • http://gokea.org/upload/editor/files/62769781317.pdf
    • http://lactopad.com/uploads/files/71488285149.pdf
    • http://llux.vn/uploads/files/14708477173.pdf
    • http://xn--12cm8caae5d9a0a0a1dxk6dd.com/user_img/files/zavurogitiboravefirin.pdf
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137befe0cb24---nomaserezoz.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=convert+png+to+vector+drawable+android+online
    • 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_off0000d78c.bin
330c13622215e0873e9909ea585ed39d02c78141eef1b576cbbfaab6dd5b9cb6
pdf-font-stream PDF embedded font (sfnt) at offset 0xD78C 10844 bytes
font_01_sfnt_off0000f053.bin
7fbb6a6b216c32fa4604df731d58b79ca432065fe681956b591271f70ce65567
pdf-font-stream PDF embedded font (sfnt) at offset 0xF053 19984 bytes
font_02_sfnt_off0001242f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1242F 16792 bytes