Malicious PDF — malware analysis report

Static analysis result for SHA-256 4542aa0f4a81ed22…

MALICIOUS

PDF

72.7 KB Created: 2021-08-28 05:18:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f7b78b5446ba5ce4ed0256363eac8c59 SHA-1: 585c861fd0426808d37746b35a7167ae5d810972 SHA-256: 4542aa0f4a81ed228adb6365ff56cb4e842cc232ab141dcf0b392e3e07f0124d
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous external URLs, many pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable binary data, offering no direct clues to its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://1984wnhs.com/clients/2/25/250e0aaa51dad033202e6c34d8602b4d/File/dinevidenusupinizofeji.pdf
    • http://ausafe.net/images/art/files/90193184416.pdf
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ffdb8a2358---22203933195.pdf
    • http://phongkhamthienhoa.org/images/files/kekasu.pdf
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160b8a11d55762---84816888359.pdf
    • http://dyglas.com/userData/board/file/2150387428.pdf
    • http://erictex.com/ufiles/files/wuxomukikigifokovutu.pdf
    • http://japan-railpass.info/images/blog//file/66965028837.pdf
    • https://pasationtravellers.com/root/FCKeditor/file/noxugunarurugulufog.pdf
    • https://osikovo.eu/webroot/img/content/files/33938753526.pdf
    • http://sujitonweb.com/userfiles/files/56237132339.pdf
    • http://stroi-sistema.ru/img/gelumakijono.pdf
    • https://parfumzone.ro/files/file/nimev.pdf
    • http://aqbnb.com/uploadfile/file/derajuneliwexosotepo.pdf
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f243eb7c762---binibapakusaxuxotukikef.pdf
    • https://solener.info/ckfinder/userfiles/files/94505193142.pdf
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/160abb66252b28---getovejakeze.pdf
    • http://drstevealbrecht.com/wp-content/plugins/super-forms/uploads/php/files/8c5a75d036a36e140080db1b463db217/vibodovom.pdf
    • http://kup-vino.cz/web/ckfinder/userfiles/files/96604591204.pdf
    • http://brmxn.com/userfiles/file/20210815120252_3bh787.pdf
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ae398c0fa---purejuzugajix.pdf
    • http://aeronautike.com/userfiles/file/kibokejoxopewizajame.pdf
    • https://wkd-uk.com/wp-content/plugins/super-forms/uploads/php/files/8792f4985831325b5d595b6d7ca760b6/fipudasenegaguvolunejija.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=hacks+for+cold+war+zombies
    • 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_off0000bbdf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBBDF 16792 bytes
font_01_sfnt_off0000d3f1.bin
a2cb50ab17367986671c8fb90d8e89d29d2af3879665487cf6c0457769d3533b
pdf-font-stream PDF embedded font (sfnt) at offset 0xD3F1 15520 bytes
font_02_sfnt_off0000fba5.bin
f2b9b8aebb882b03a2280693de59d939642a30ee6cda3576171b6b6c9bd77d5c
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBA5 10804 bytes