Malicious PDF — malware analysis report

Static analysis result for SHA-256 afd4a36fec02f05b…

MALICIOUS

PDF

73.7 KB Created: 2021-09-09 02:04:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 4cac254d1fd4696b30cb2002d31dbbb3 SHA-1: 007de278e92df33df893bc34156483f79956ad78 SHA-256: afd4a36fec02f05b41564bc51845ae99b78f61f0a206325d2d85a9266689c8a1
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised WordPress upload directories and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The primary attack pattern involves luring users to click on these links, which are designed to appear as legitimate documents but lead to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/161349b042830b---zodudiberim.pdf In PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/f54338815ee78cbf30cd76b144542b0f/74534774683.pdfIn PDF document text
    • http://haustechnik-hagenauer.at/nesexijosarusifalalujeje.pdfIn PDF document text
    • https://organicearthfiji.com/documents/file/35224615380.pdfIn PDF document text
    • https://samirkumarpaul.com/ckfinder/userfiles/files/87598403577.pdfIn PDF document text
    • https://simon-daulte.com/ckfinder/userfiles/files/nijifajupapile.pdfIn PDF document text
    • http://wmc21.com/ckupload/files/bisefot.pdfIn PDF document text
    • http://sor1310.com/userfiles/file/legowofumumekawopuji.pdfIn PDF document text
    • http://ffarchitettura.it/userfiles/files/jaweleruze.pdfIn PDF document text
    • https://matfplayer.com/calisma2/files/uploads/jutovefave.pdfIn PDF document text
    • https://sogelec-eng.com/files/ckfinder/files/96940859393.pdfIn PDF document text
    • http://mirutte.com/newsfiles/files/netid.pdfIn PDF document text
    • http://chixue.com/uploadfile/file/20210907073231.pdfIn PDF document text
    • https://ms02bet.net/contents/files/mimadatibonubugitis.pdfIn PDF document text
    • https://skinrepublic.vn/webroot/img/files/3740263132.pdfIn PDF document text
    • http://ubest.ru/images/file/72250858155.pdfIn PDF document text
    • https://tttinox.com/upload/userfiles/files/70454770055.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/161340d68e7302---7276605173.pdfIn PDF document text
    • https://yensaovinastar.com/media/files/suxolomeniju.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/16131d50a54b91---sowisilewesinubowapoxu.pdfIn PDF document text
    • http://tacchigroup.com/public/thread/risorse/file/tiginukenisegelojazi.pdfIn PDF document text
    • http://ambulatorioveterinarioilprato.eu/userfiles/files/27100428758.pdfIn PDF document text
    • http://stroi-sistema.ru/img/75164734080.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=free+live+tv+app+apkPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c0a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0A5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d8bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8BB 9988 bytes
SHA-256: a1a76ec1e75f99722a282e55ec2264a1fbeb654db2aa28b1bd06656c17835d14
font_02_sfnt_off0000eefc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEFC 16596 bytes
SHA-256: a1a193a2cb086ceb6d25b8f4a67ea219ae0907ce824fa4e07757f226a9a3fd1d