Malicious PDF — malware analysis report

Static analysis result for SHA-256 936345cd881b44be…

MALICIOUS

PDF

77.1 KB Created: 2021-08-24 03:33:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4b99ea69c5c03d68944796bf57c37aa6 SHA-1: c506087f5c86165ec514ba292bba7b38a93ada08 SHA-256: 936345cd881b44be64b1be69e7d1ff00f98b8389b79c615e78e4437bbaf2028b
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external URLs, many hosted on compromised CMS platforms. The presence of these links suggests a phishing or malware distribution attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://baocaosudanang24h.com/uploads/image/files/52425714526.pdf In PDF document text
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/ae87fc93c113055224ec2cabe1f5aa6d/60750040613.pdfIn PDF document text
    • http://longvu.vn/Images_upload/files/wotipi.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/m304bm7su80i5ob6gvacrdjjuc/45972838285.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/fea31f70832416ef8b8e9cdd1b66bc71/88465502984.pdfIn PDF document text
    • http://technology-mp.it/userfiles/files/40599795291.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/dnm4avl48dcaebpctccr5s6q9r/vakusixabaregurefexinu.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/4b0ht5gg311uur77fs6l7abkac/zilexofun.pdfIn PDF document text
    • http://goldcoil.com/uploadfiles/files/9152889963.pdfIn PDF document text
    • http://limitlessillusion.com/wp-content/plugins/super-forms/uploads/php/files/1df1ba0021c5a858e290cf0ab4737ddb/povofuwasukubero.pdfIn PDF document text
    • http://ieeepes-thailand.org/app/webroot/files/files/xaguzilumodin.pdfIn PDF document text
    • https://icicle-mountaineering.ltd.uk/ckfinder/userfiles/files/58334917340.pdfIn PDF document text
    • https://blindnow.com/userfiles/file/3191726983.pdfIn PDF document text
    • http://babywagen24.de/userfiles/file/8148173804.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/657832484152b119e8c142aa0295b803/norovufozeruwiposome.pdfIn PDF document text
    • https://fotovipvercelli.it/file/67498438794.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/cd8c4363f098c1ed00fa7fb1468658c8/dejawakukedi.pdfIn PDF document text
    • http://joelcsimonesq.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/99479034516.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/de6a5f3a009ca8241f1c172c3fa24728/lixipiwibobepekilemugi.pdfIn PDF document text
    • http://hwayoung.kr/upfile/files/difoxilowuzefutalazijox.pdfIn PDF document text
    • http://absigorta.com/E/file/31504997462.pdfIn PDF document text
    • http://gd-weimi.com/upfolder/e/files/20210805235258.pdfIn PDF document text
    • http://www.empresshasnoclothes.com/siteuploads/editorimg/file/79540432836.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16085d8b840a02---16624589261.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=tables+1+to+20PDF 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_off0000cc7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC7B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e492.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE492 10200 bytes
SHA-256: 1ad0a8233545cd3c37e8957e2bd09d01177628391b2ae821a1b5c5d44a2a0a72
font_02_sfnt_off0000fbba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBBA 16296 bytes
SHA-256: 5dfe8183b20ba48e72c19db03e8cf953ead217f7096ff3f48aa51a5b10c8abe9