Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6c91f693d438507…

MALICIOUS

PDF

68.5 KB Created: 2021-09-28 05:52:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b9ec0c147bcdc2361a678f11d65170ca SHA-1: ce88f7c2bdf2b6303b313ec8c7ad02e5b66d6b97 SHA-256: c6c91f693d438507122fd8fd118a449498bc6b6aa5fe7086d5882bb33b11dcbc
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, utilizing compromised CMS uploads and disposable hosting to distribute PDF files. The embedded URLs and the nature of the heuristics suggest it is designed to lure users to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://lindendirect.com/tempimg/file/39796598237.pdf
    • http://thebookmarkcafe.com/uploads/files/nugugaseb.pdf
    • http://cottoneauto.it/userfiles/files/buxalu.pdf
    • https://goooinggroup.com/userfiles/files/20210918_063007.pdf
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/2920a744971b2bc5fb6aee6fd09129d9/27013800134.pdf
    • http://1yunnan.com/ckfinder/userfiles/files/xukimugobuvavalamagu.pdf
    • http://alteredcompta.com/buddha/ckfinder/userfiles/files/66507907088.pdf
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/c2a79d0aa0bdd1548dd5b4b2b6fdbee5/mimakuvexosakiwimik.pdf
    • https://generalaudit.pl/eurostyl/photos/file/jugewojafiterisasikegipe.pdf
    • https://vishalahospitality.com/ckfinder/userfiles/files/55552685233.pdf
    • https://infrapanel-alegjobbfutes.hu/userfiles/file/fovuzaveref.pdf
    • https://ocw.tw/uploads/files/vajisazodevojipelen.pdf
    • http://metisentry.net/ckfinder/userfiles/files/68535419389.pdf
    • http://nuovojob.com/userfiles/files/52810182045.pdf
    • https://rdsdealers.com/ckfinder/userfiles/files/tofenoke.pdf
    • https://morabia.fi/images/file/56839171650.pdf
    • http://packturf.fr/files/57305416253.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614a2e601b7db.pdf
    • https://fizjolech.pl/userfiles/file/8132773437.pdf
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/736eabec2ed4a893234af22adb016987/93449868695.pdf
    • https://0800-707-808.com/upload/ckfinder_temp/files/20210925131654.pdf
    • http://mywayrtk.info/userfiles/file/milibonoxope.pdf
    • http://fbrasil.com/userfiles/file///88490297900.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=watch+lovecraft+country+online+free
    • 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_off0000aea6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xAEA6 16792 bytes
font_01_sfnt_off0000c6b8.bin
ff2cf8e80cf43b44f4ab301d6cefb787e809b9deb9d535bee7f3da3eae0a057f
pdf-font-stream PDF embedded font (sfnt) at offset 0xC6B8 15252 bytes
font_02_sfnt_off0000ecd1.bin
e218f98303a5be9e8eacbc3cf799af3efc1e0ec9e2b9b0d6c0a21f62f5b161c3
pdf-font-stream PDF embedded font (sfnt) at offset 0xECD1 10536 bytes