Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b118fa96e3d4a10…

MALICIOUS

PDF

83.3 KB Created: 2021-09-12 18:19:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4aa515303f3303a59cba6697b2ce0120 SHA-1: b5446438f0be8327351361b048bafd55a5f338b8 SHA-256: 8b118fa96e3d4a10eabdc0cc9ee4b83f9c6d5163349551ce066a8f6e43826422
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous external links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm or SEO poisoning tactic. The presence of a 'download' button lure and ClamAV detection as 'Pdf.Phishing.Trojan' strongly indicates a malicious intent to trick users into downloading further malware. While no scripts were directly extracted, the overall structure and heuristic firings point towards a phishing or downloader campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://synerhu.ru/uplcv?utm_term=download+novel+alnira
    • https://www.leasing.net.in/ckfinder/userfiles/files/votijib.pdf
    • https://albertoangel.sinecsas.com/ckfinder/userfiles/files/79248477169.pdf
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/16136a06a1e9d4---1140625538.pdf
    • https://www.theknowledgeonline.com/files/lib/ckfinder/userfiles/files/jirebunimipijag.pdf
    • http://xn--or3bi2da319p.com/upload/fckeditor/file/potob.pdf
    • http://eko-gospodarstwo.eu/files/file/72401387221.pdf
    • https://motoquadro.de/userfiles/file/61657859482.pdf
    • https://vrindaindia.com/php/joseph/uploads/file/8723570447.pdf
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/161313c42a3565---rokakirosusuvozozimopir.pdf
    • http://morakothotel.com/file_media/file_image/file/74050898233.pdf
    • https://casaalu.com/luutru/files/71569735770.pdf
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/d02da5c5e7b44d97869baa9e0c1f3586/94127856793.pdf
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/161329403dae60---28662836791.pdf
    • http://pushgroup.lv/userfiles/files/dotinugevazenabatem.pdf
    • http://precisao.org/files/files/19623662896.pdf
    • http://mintaialuminum.com/d/files/13782180137.pdf
    • http://rideco.hu/upload/file/kabevopusufizapadivow.pdf
    • http://sapientgenerator.ru/files/userfiles/files/78954082457.pdf
    • http://hvezda-pardubice.cz/files/file/40507667061.pdf
    • http://kooijobs.in/ckfinder/userfiles/files/77082142674.pdf
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/161323db01448c---tubiwa.pdf
    • http://juentai.com/userfiles/files/70495472181.pdf
    • http://www.ecostroyservis.ru/File/vewojejodonikebipi.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_off0000e0b7.bin
d12a326d81780a1d158bd894b2fa4f54b201d3415eb7a6dcc7848753a96ddbe3
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0B7 18620 bytes
font_01_sfnt_off00011188.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11188 16792 bytes
font_02_sfnt_off0001299f.bin
f1b09238c9da34c5d40267a067c03568eb17d3e12a6aa88cb84b78cc76aba5f6
pdf-font-stream PDF embedded font (sfnt) at offset 0x1299F 10128 bytes