Malicious PDF — malware analysis report

Static analysis result for SHA-256 d170cde4c520645a…

MALICIOUS

PDF

78.0 KB Created: 2021-09-06 08:05:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 691f855c7ba21a5f16ba990f5fedef2d SHA-1: 281c0c49abafc33d8c2a4201c658d25ee6024ce8 SHA-256: d170cde4c520645aa34d0d00e31e2af17f1255d8ae7bf9afe692760686659eef
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for initiating malicious actions within PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9829

Heuristics 7

  • 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.
  • 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://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/ejqi9ifp3aaid1ieob0v63paeb/36363746844.pdf In PDF document text
    • http://emrc.ie/upload/imagecontent/file/kejajabimeperozatil.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210902074855126.pdfIn PDF document text
    • http://esipro.lu/userfiles/file/81770730287.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/e564dc4ea1a07acb72f8ff244f546c42/96915081841.pdfIn PDF document text
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/ffc7e627064f00df95aad6d2d3fe5d28/davumujarin.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/lunuxodu.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b0f3c6b58bc---bozagobono.pdfIn PDF document text
    • http://jr-bang.com/uploadfiles/20210629164936.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/u6rramef1p2fot4vfkt19cl2rs/jagazuz.pdfIn PDF document text
    • https://srilangkapools.com/contents//files/65081544398.pdfIn PDF document text
    • http://africansafaris-spain.com/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/wizumaguwonebapejavux.pdfIn PDF document text
    • http://syuncyoku.jp/upload/file/fuwuninosuwubulanevuliki.pdfIn PDF document text
    • http://mpti.ru/userfiles/file/6175533385.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/1c5oj2838q8dsuvd9osuqpv3bs/feduxodenirejadonup.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/10587432909.pdfIn PDF document text
    • http://flynewsletter.com/uploads/file/mabuvoreloriwoli.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/a3acf6152d6b088135cc5ad766f8c04e/liludob.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dc37d72d178---98194520597.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9910ac262---tajudufabepukasemoju.pdfIn PDF document text
    • http://volvo-cars.jp/js/upload/files/titerapiruruwiviwemikufuv.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/98hs7cmh8ra1tnugtsurotmc02/77956216790.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/35c945a290ede4349d22ad13032829d2/70966387034.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8ef44ca21b---20358032505.pdfIn PDF document text
    • http://change4best.ru/upload/file/sowowabeduvidos.pdfIn PDF document text
    • http://sevenseahotel.com/uploads/images/files/44380774798.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=monsieur+pouce+va+%C3%A0+l%27%C3%A9cole+pdfPDF 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_off0000c413.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC413 11048 bytes
SHA-256: 9914bcf896642b4aae82c4a8452135897b485c85a1a2f6ef58a9e251bbc2b6bc
font_01_sfnt_off0000dd3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD3B 20676 bytes
SHA-256: 55028bea93b9666fc654b4c02e74a537c5e2e917dc6bb38dd836e4ed5ffe2db4
font_02_sfnt_off00011040.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11040 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1