Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5281b37a2975b87…

MALICIOUS

PDF

80.4 KB Created: 2021-06-28 01:41:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8fbdcbea3aad1765163c534cba945951 SHA-1: f336a939e7eb02c31929375c49ae498a4d2ee4af SHA-256: f5281b37a2975b87d6460b66c1c21d7e94376c6de5aa5e3a1c510ba2f106af96
196 Risk Score

Malware Insights

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

This PDF document is flagged as malicious by ML classifiers and ClamAV, and contains heuristics indicating it's a link farm and a remote-support tool lure. The document likely aims to trick the user into downloading and installing a remote support tool, which could then be used to gain unauthorized access or deploy further malicious payloads. While no scripts were directly extracted, the presence of numerous links to potentially compromised sites suggests an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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://waukeganeast1980.com/clients/877304/File/13930832718.pdf
    • http://4998horo.gmmwireless.com/contents/files/17761259551.pdf
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/39rj3g0m49oh61d2noilsrs567/57087500819.pdf
    • http://quangcaosms.org/media/ftp/file/17290717119.pdf
    • http://qhzs88.com/admin/fckeditor_upfiles/file/2021062520221680554.pdf
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/9eff71faf436495ad88eceeb2f3d9f08/82871590254.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d470d5b85a7---zarojizero.pdf
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/16086146325e25---49634526543.pdf
    • http://koreaseals.com/ckfinder/userfiles/files/tedogok.pdf
    • http://wjvanderheidedienstverlening.nl/uploads/file/simivuwa.pdf
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c4878bf986---53576648343.pdf
    • http://mytmbc.org/fckimage/file/54876705446.pdf
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609e1efdeb3f6---63173137346.pdf
    • https://www.qlsny.com/wp-content/plugins/super-forms/uploads/php/files/00745ffc52dc622bdcc7e5e882825bff/wexemapepamikosorogapefe.pdf
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087d78f175a8---mutijo.pdf
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a73af12e98d---53549736385.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0db60ffc4---7538865584.pdf
    • https://stop-remont.ru/ckfinder/userfiles/files/vegevulepopupudiz.pdf
    • https://systematix.pl/userfiles/file/69148209826.pdf
    • http://tcsm62.org/uploads/news/file/reveberiruzojilabidafi.pdf
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/071ea80042ca01135d00d866a0ab33f3/tavuvajaboporuga.pdf
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/5a7894bdb556df2491b32d719c7aefc4/85878494913.pdf
    • http://retroldn.com/userfiles/file/32932112513.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606ccf8059904---3068123982.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=motorcycle+with+carburetor
    • 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_off0000d894.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD894 16792 bytes
font_01_sfnt_off0000f0a6.bin
e614a0e4ef0d2d2e470d4475ed5a1b9e8f26135bc8cd26e6f85f854b5f882bc0
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A6 16708 bytes
font_02_sfnt_off00011c35.bin
76c0b2613e730cfd2877fd436fbd7d3caff2919689bf1c9e8a803a2862cdd0b3
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C35 10488 bytes