Malicious PDF — malware analysis report

Static analysis result for SHA-256 99473b072baddbc7…

MALICIOUS

PDF

72.7 KB Created: 2021-09-28 07:31:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7aac7ee58aaf3742335014d56e7fd7a6 SHA-1: b78e00021dacaf2222c35e9b5d85a20fa97e3832 SHA-256: 99473b072baddbc788c1fa71848a51d8e24bb748e45bc48a5155ae2dceeb3042
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier, indicating malicious intent. It contains a link farm with numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The presence of external URIs and link farms strongly suggests the document is designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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=how+do+i+turn+off+live+caption+on+my+phone
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/58930774608.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/3d64917280abcde5fcae7285a920ea9b/zewilujenad.pdf
    • http://raegcafe.com/uploads/files/53996693538.pdf
    • https://accesoriosalmayor.com/images/userfiles/file/kagujofotinip.pdf
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1614b192aaabd9---vigapugowejij.pdf
    • http://solo-reisen.com/media/images/file/vawazawazozudelelibus.pdf
    • http://www.tivafa.hu/upload/file/63731412359.pdf
    • https://tepihtrava.rs/files/16284554655.pdf
    • http://air-ned.com/uploads/files/nudobusowukovor.pdf
    • http://seowonbattery.com/files/fckeditor/file/1840572998614e0a5e1fa24.pdf
    • http://vektor-bezpeki.com/userfiles/files/62652523177.pdf
    • http://www.jindatunnel.com/up_files/file/91617688086.pdf
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/qqcqn2dncvk599brtg9aa900h5/2935631700.pdf
    • http://herfon-machinery.com/images/ckfinder/files/20210908183156.pdf
    • https://shian-jin.com/UserFiles/files/85519898701.pdf
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614acabb328da---sijimizewuxujajuto.pdf
    • http://ohadalegistrocbarter.com/ckeditor/uploads/files/23854950420.pdf
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/fc501d4b7636f7d8c90ec38e18b657da/71849052905.pdf
    • http://dlabiura.kbo.pl/ckfinder/userfiles/files/rukofizepogiwavijepel.pdf
    • http://ok-poland.com/userfiles/file/39833059158.pdf
    • http://cassotech.nl/site/data/ws/files/85853536125.pdf
    • https://nepalipublisher.com/ckfinder/userfiles/files/wafebapefanixisubudux.pdf
    • http://easyreturn.store/userfiles/file/73643850199.pdf
    • https://tekartltd.com/upload/files/93640292926.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_off0000b581.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB581 16792 bytes
font_01_sfnt_off0000cd98.bin
7e5fabe99f3d579b6aa524ca9c5d9038bacdb223e23c792fa4f6040d664ca26c
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD98 11072 bytes
font_02_sfnt_off0000e733.bin
a2c60a923de5cd5c6e8eacad318137621439f68d0bcd887e49165e8551ea60f9
pdf-font-stream PDF embedded font (sfnt) at offset 0xE733 17684 bytes