Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8ac34a9d3f0fc67…

MALICIOUS

PDF

87.1 KB Created: 2021-06-26 01:46:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4d7cc5e3d2b312dd72a901d1afecee14 SHA-1: 0e118b2ddf95316636acbde8fdd6fca71dba9bee SHA-256: a8ac34a9d3f0fc67a7f8edf1a772e3f5ba008dbab66a2673e5dfa8acc65efca0
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress upload storage and disposable hosting, with numerous URLs leading to other PDF files. The document body was unreadable, but the structure and URL analysis strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 https://clubsportedinburgh.org/userfiles/files/44236629902.pdf
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/6c191297e0514d460a6779950ed0723e/62057762295.pdf
    • http://bassbasement.org/userfiles/file/17273442286.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a56bbb28ed---93785983839.pdf
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/5702ca87df4b9dae235e3903b23e8c5e/36440492510.pdf
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8f49b8b63e---bibonelimirexaxelo.pdf
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/e18e38a3eca668e68bd519b62d06bddb/66866501886.pdf
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f053238ead---desotarevebijifezamikana.pdf
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb0bdc0be2f---mutasalab.pdf
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5f5d2cced502b6685d033cdfb3db0541/32355836818.pdf
    • https://gea99.com/ckfinder/userfiles/files/39741590009.pdf
    • https://inverpalmas.site/aym_image/files/36426972049.pdf
    • http://citra.cl/userfiles/file/gizoxuk.pdf
    • https://dhcom.vn/userfiles/file/dulukogosu.pdf
    • http://chiengthai.com/file_media/file_image/file/ruwuvukero.pdf
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160a0f2f425d5a---runat.pdf
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/a591b155f4c15bb6c8ec3f22d743e856/zosugufojet.pdf
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609d81cb06538---18508698733.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba438f6e254---kixurazovaposasusuxa.pdf
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/6371e70ee89dca13ad4b883153420a03/jubeze.pdf
    • http://hongshengfish.com/uploadfiles/20210513/2105132203173015254epz1gl7791f.pdf
    • https://himalayanthailand.com/image/upload/File/35351791459.pdf
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1607ed26140663---57492882981.pdf
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/fe335407c9261a11b6e5b60ced457247/lezexevibimozofevanenek.pdf
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b729c0c4a5b---4698919871.pdf
    • https://readandenjoy.ae/userfiles/files/lepawumegidaruwigubij.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=mindset+of+growth
    • 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_off0000f3ef.bin
fdf33ed4f52f22e4658fb2e9433ea86d5e17b30d31d5ad00aeffabcc9cee6675
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3EF 16804 bytes
font_01_sfnt_off00011f88.bin
a76e8a08a2d82627f80d8b3f91ea48c6c75b7f3cd21b3ec9914ecdf38d3242ab
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F88 10504 bytes
font_02_sfnt_off00013735.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13735 16792 bytes