Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fd1da5cfa95728f…

MALICIOUS

PDF

88.9 KB Created: 2021-06-28 05:47:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4795ff9a17e07fca5f9138ff9eb236fe SHA-1: 58d17b1558df63929759413cccde196c3390a44d SHA-256: 4fd1da5cfa95728f6416b30969ab877bea326b958d34fa92e94c1fb52ddae9ee
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to compromised CMS uploads and disposable hosting, designed to redirect users to potentially harmful sites. The presence of multiple external URIs and link farm heuristics strongly suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://inwebjor.ru/uplcv?utm_term=queens+of+animation
    • http://volamtuyetthe.com/userfiles/file/xisibevidivemuzezeg.pdf
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/aca207e1e1ef4dc3bdec1f221feb8d7c/rotonaso.pdf
    • http://dakmoto.cz/obrazky/file/posigok.pdf
    • https://electrabicycles.pl/app/webroot/uploads/file/16235338500983.pdf
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160bba13e173f3---xabumas.pdf
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b040c9cfd8a---rafekovuvovidev.pdf
    • https://transport-vehicules.fr/userfiles/file/xopuxefujizutuzewajuji.pdf
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/921aec03c09c569fce0e0e636e4abba3/wavalopulijawef.pdf
    • http://ampletrekking.com/userfiles/file/71025751275.pdf
    • http://vimar.ua/userfiles/files/69109937524.pdf
    • http://hakkabrothers.com/userfiles/file///vuzis.pdf
    • http://aj-logistics.com/stock/userfiles/file/54711686934.pdf
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/254a05171732722fd729175ceb3c50a7/golunuligut.pdf
    • http://bidmitt.com/img/files/file/womiluwifixori.pdf
    • http://zuche0551.com/upload/file/tiwusode.pdf
    • https://itracmediav5.com/ckfinder/userfiles/files/20740842581.pdf
    • http://asbu.net/uploads/FCK_files/file/wijaxiwawidivenib.pdf
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b47efbd9efc---pelenijefav.pdf
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ab1e02cfe09---pabolabegixetarezoferose.pdf
    • http://gdgom.com/upload/file/210611075145696838k3fxrn2dtr3r.pdf
    • http://korean-school.hu/hangul/userfiles/file/41695324965.pdf
    • 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_off0000fab2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFAB2 16792 bytes
font_01_sfnt_off000112c4.bin
84bca0caa0ba06e8b024dc233c42e001b58af63e5e71c59b3020c4fea4c900cb
pdf-font-stream PDF embedded font (sfnt) at offset 0x112C4 17092 bytes
font_02_sfnt_off00013ef7.bin
0dce6da27493fbc7404e8144c30cfac0e5feb63c29f501c30ca64ce80b02cdfa
pdf-font-stream PDF embedded font (sfnt) at offset 0x13EF7 10388 bytes