Malicious PDF — malware analysis report

Static analysis result for SHA-256 5fae5241abc144a5…

MALICIOUS

PDF

84.1 KB Created: 2021-07-03 12:35:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: df86031377b2c903018107c9c999eb7e SHA-1: 1f46bdce4783e4a54afd69c333b8dc0eec04a8e6 SHA-256: 5fae5241abc144a58fd7c674bd956a0b2a2cc299e0a8f95986446c05c7085e39
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of embedded URLs, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The primary function appears to be acting as a link farm to redirect users to potentially malicious content hosted on various domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://massvt.sk/editor_uploads/system/files/xasak.pdf
    • http://www.alexgis.com/siteuploads/editorimg/file/99394227531.pdf
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/970a76910155572eb5090d438030c2d9/81917307297.pdf
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b83d8b20daa---62594787129.pdf
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160dc15b0315ee---31890428785.pdf
    • http://meruzhankhachatryan.com/app/webroot/files/file/kotadufufunus.pdf
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608142b2f038a---7062219362.pdf
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e94926644c---senudutedugazafi.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609fbc042ce50---37069285559.pdf
    • https://circolodelpistone.ch/userfiles/file/memakajejotisunimuk.pdf
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/9f700e23a16a7abc5398b49db4e53caf/81225614599.pdf
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16085cde07e040---xinajagijuvugosigigitidi.pdf
    • https://kimtuong.vn/isc/public/files/fckupload/file/worug.pdf
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083221ae2cc2---debaxotawe.pdf
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/ef481b685d2df845868a3535d916c922/55369026501.pdf
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/7f7a1424755c9d8697b4850aa6dd4a62/99367144318.pdf
    • https://lamaisonducoeur.ca/upload/editor/file/1397847454.pdf
    • http://ccswcd.com/userfiles/file/tavafitovex.pdf
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/l28reuj064utrl4fk5vid79lv0/16631054588.pdf
    • http://doks-films.com/pcms/content/file/72403985037.pdf
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d99dc69ab69---bujewekoxeb.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=l+letter+words+in+english
    • 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_off0000e7fb.bin
e0e8071d0f963cfc0610d05473f4ae4e64419de01cf896d89665171a1fd95d53
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7FB 10408 bytes
font_01_sfnt_off0000ff42.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF42 16792 bytes
font_02_sfnt_off00011754.bin
6242b40c644846210dd529e62d1fb4a40dd252ef22d13566d6e93d6112aae188
pdf-font-stream PDF embedded font (sfnt) at offset 0x11754 17004 bytes