Malicious PDF — malware analysis report

Static analysis result for SHA-256 6aa9cb846b42a309…

MALICIOUS

PDF

80.5 KB Created: 2021-09-08 00:52:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: da39776106a8175f47938336c09c91a1 SHA-1: ef656d7b7f8c1d9177790ddf0792753ccbb7b9ad SHA-256: 6aa9cb846b42a30922fc1b8b049ac28694071bbbb9606b587756615b62fe086c
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically identified as a phishing trojan. Heuristics indicate it functions as a link farm, hosting numerous URLs on potentially compromised or disposable domains, designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, suggesting an attempt to hide its true purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://bibonatura.com/ckfinder/userfiles/files/lulogozukexezituf.pdf
    • http://ahcxdq.com/uploads/file/300056405013.pdf
    • http://deepakbatteries.com/uploads/file/rerexidunubimafatozomave.pdf
    • http://thaisomboonautopart.com/userfiles/files/mafuziroxiweva.pdf
    • http://nessium.net/userfiles/file/59103896529.pdf
    • http://poaglasses.com/uploads//files/202108071000286719.pdf
    • https://farmstead.tw/farmstead/upload/files/nokuguvakan.pdf
    • https://abeess.com/userfiles/file/mazatojarirapejurufusuj.pdf
    • http://praconsulgroup.ru/pict/file/gobeziza.pdf
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070a421486e9---65333028945.pdf
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160d370b39ac8f---zaviriliveliriramomujepu.pdf
    • http://geteffective.biz/uploadfiles/file/65504147999.pdf
    • http://lltsg.com/uploadfile/file///2021062813422453.pdf
    • http://www.alquilerbares.com.ar/wp-content/plugins/formcraft/file-upload/server/content/files/160841e0e936e4---gazexoz.pdf
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/pfkiku81fnulj3q6fc6h6i35s2/26850992415.pdf
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/7aec78bb11fcc6f84e61a9925244da26/73578481681.pdf
    • http://ressourcengarten.de/azubi/userfiles/files/semilekid.pdf
    • https://itchanoi.vn/uploads/news_file/gufidapimekawalefaka.pdf
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c213b5173fb---titoxo.pdf
    • https://aartipalette.com/userfiles/file/goboxazolukufitigevagej.pdf
    • https://keralatemples.info/ckfinder/userfiles/files/95268587731.pdf
    • http://studiostocchi.eu/userfiles/files/ditopivonogosifu.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/0b1d48b22ce51dac6cf9d9a8a14a9d4c/feverokebixufuzaf.pdf
    • http://zae.me/datafiles/file/26119011149.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=singer+florencia+62+manual+en+espa%C3%B1ol
    • 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_off0000d2e3.bin
02668a3e156405a552ef7ee202e7030dedb8761595030409443e9c09bea7bddf
pdf-font-stream PDF embedded font (sfnt) at offset 0xD2E3 17728 bytes
font_01_sfnt_off00010000.bin
6a6037b0928b27271e120fbf1a9565c0f8af6d2702cff369decaf3e99acabb53
pdf-font-stream PDF embedded font (sfnt) at offset 0x10000 11396 bytes
font_02_sfnt_off00011a9c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A9C 16792 bytes