Malicious PDF — malware analysis report

Static analysis result for SHA-256 d664634664482026…

MALICIOUS

PDF

74.8 KB Created: 2021-07-01 21:57:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 1dfa6b8075028ac98603240c207c01e9 SHA-1: 63d802415ccc9a355971fd80a7aedfea456bca7f SHA-256: d664634664482026d343e529bbb125cea6f28341c97172bff6110be436b82480
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a malicious PDF by ClamAV and an ML classifier. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users. The PDF also functions as a link farm, pointing to numerous compromised WordPress upload directories, suggesting an attempt to host malicious content or phish users. The presence of embedded JavaScript indicates an intent to execute code within the user's browser or PDF reader.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/16090e13b834c6---mevosupumun.pdf In PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070dfcd62b46---4825847925.pdfIn PDF document text
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/016d8ba60b22f24c02ba8127d3ce2860/13081771412.pdfIn PDF document text
    • https://konferencii.ru/js/ckfinder/userfiles/files/wotap.pdfIn PDF document text
    • http://omak1968.com/clients/71178/File/niradupogolurowuwugupa.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160c29b5205811---sorixinokufupeketoj.pdfIn PDF document text
    • http://madonnina.info/userfiles/files/febukabufixom.pdfIn PDF document text
    • http://hk-sai.com/ckfinder/userfiles/files/dekixatovedab.pdfIn PDF document text
    • http://toyotarentcar.net/FileData/ckfinder/files/20210628_56B44B261A6E9FA8.pdfIn PDF document text
    • https://bandai-k.com/userfiles/file/57544547093.pdfIn PDF document text
    • http://classicalgardenornaments.com/uplds/file/gulimuxalen.pdfIn PDF document text
    • http://kco.su/userfiles/file/gimafanoxegugunosut.pdfIn PDF document text
    • http://esthebel.de/userfiles/file/9588703803.pdfIn PDF document text
    • https://e-lightingcontrols.com/wp-content/plugins/super-forms/uploads/php/files/8306b57f4a3bbd386e5baa86d4d00f3f/bibifujereluso.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607589c87e2c9---zulibexokinu.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/22svfifno68n8nhufi49lvvp30/vanupatugobupusun.pdfIn PDF document text
    • https://airshow-bg.com/file/zubejo.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/8f5299b2c6e185bcac2437450def8782/51686678564.pdfIn PDF document text
    • http://druckmaschinenservice.com/uploads/fce/files/pokazusanenuvat.pdfIn PDF document text
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c91235d39b---lowazoxazonin.pdfIn PDF document text
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16088e6c3d101d---lepabepamo.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/16082e7550e769---49792690086.pdfIn PDF document text
    • https://myphi.biz/nbloom/fckuploads/file/86489281824.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=when+to+use+the+word+whosePDF 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_off0000c240.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC240 10224 bytes
SHA-256: 3e7964416c4b894485f97bf9ec11dacd0ffce9c1ab98fb2e51105f64e2ac0c49
font_01_sfnt_off0000d938.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD938 16580 bytes
SHA-256: 77617eca790d99347d757d3e2b5a4250b1a702bdc1d27523228e71cd39e0c15e
font_02_sfnt_off00010453.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10453 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1