Malicious PDF — malware analysis report

Static analysis result for SHA-256 11cdd94721c64488…

MALICIOUS

PDF

82.3 KB Created: 2021-09-16 10:29:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6c459f31f5da569c3c76b6451f6fbc72 SHA-1: 5be2bdc9d2ab9ebad68481b268d16779c6ec515c SHA-256: 11cdd94721c64488e8587ea50622f5a2f675e0b2a725034c5cf3228aaf72a106
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics indicate the document functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS platforms. The presence of numerous PDF links and the use of disposable hosting suggest an attempt to distribute malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9940

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://bartonsteel.com/tony/barton/ckfinder/userfiles/files/48268457124.pdf In PDF document text
    • http://tnmetalworks.com/images/files/wixud.pdfIn PDF document text
    • http://www.boldino-hotel.com/ckfinder/userfiles/files/45396319597.pdfIn PDF document text
    • http://knx-shop.ru/admin/ckfinder/userfiles/files/85162720014.pdfIn PDF document text
    • https://22importexport.com/eimages/file/20546476961.pdfIn PDF document text
    • https://vpmemorial.net/images/file/29538106805.pdfIn PDF document text
    • https://pastelbuilders.com/userfiles/file/27008360464.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613054dbed7a4---18006487359.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/7el550s293lmkfpmnnuecv0v91/70791427950.pdfIn PDF document text
    • http://mdtrend.hu/files/file/sufanabipawuwutejo.pdfIn PDF document text
    • http://cestovni-postylka.eu/userfiles/file/24258612542.pdfIn PDF document text
    • http://bloemenwinkelindex.nl/images/uploads/kibimonunowowodirejozo.pdfIn PDF document text
    • http://sutipatika.hu/userfiles/files/60438669370.pdfIn PDF document text
    • https://euchebnici.com/img/file/sageruzulezisi.pdfIn PDF document text
    • https://watertorens.nl/userfiles/file/8671815134.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/94398780277.pdfIn PDF document text
    • http://abwpetersburg.com/uploads/files/5780879132.pdfIn PDF document text
    • https://happycondo.leaddeehub.com/userfiles/files/fugar.pdfIn PDF document text
    • http://vsrru.ru/userfiles/file/25817339080.pdfIn PDF document text
    • http://tevukasveza.lt/ckfinder/userfiles/files/69259912477.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/161428817609c7---deragurebipasusubasage.pdfIn PDF document text
    • http://vladekoservis.ru/files/mazowuseli.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=block+city+wars+free+downloadPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c476.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC476 10816 bytes
SHA-256: 68eeb1c99b155370eb47372ef8b3cbdb11f483cceb5e0141d187a1b3fba86dd1
font_01_sfnt_off0000dda4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDA4 17852 bytes
SHA-256: 25c9939b35af857bced878a9552656c3944f1dc1e428cfb2ebca898683fc5a56
font_02_sfnt_off00010bbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BBD 16772 bytes
SHA-256: 471db773b9a233a641bcf9a9fde49fb1a58120df87dd44cb752e7572c1f22495
font_03_sfnt_off00012397.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12397 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1