Malicious PDF — malware analysis report

Static analysis result for SHA-256 79864ac544584e39…

MALICIOUS

PDF

83.5 KB Created: 2021-09-17 10:58:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: a8280bcf032855bdc3d4dad9ecd519a5 SHA-1: b1d87f5522c9be15aa26a12460383d5b999267c8 SHA-256: 79864ac544584e39f7b021dd882a48d39ef36a763772d171630b30af96aa9dd5
156 Risk Score

Malware Insights

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

The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF contains numerous links to external websites, many hosted on disposable domains or compromised CMS uploads, characteristic of a link farm used for phishing or malware distribution. The presence of a compromised WordPress upload link further supports this. No scripts were extracted, but the document structure and URL patterns are indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://straps.by/ckfinder/userfiles/files/26615722669.pdf In PDF document text
    • https://scalper.ir/data/files/file/28259557322.pdfIn PDF document text
    • http://cokhixnktientien.com/Images_upload/files/51414338578.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7d3faeda9---23258489000.pdfIn PDF document text
    • http://marcth.pl/media/fck/file/guretisazidijodewade.pdfIn PDF document text
    • http://bettynblue.com/upload/fck_img/20210906/file/88041290634.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b647da3687---60080854731.pdfIn PDF document text
    • https://xn----8sbcehyodmtf1czh.xn--p1ai/userfiles/file/26234840982.pdfIn PDF document text
    • http://navigator-nsk.ru/userfiles/file/monotatakevewejetamir.pdfIn PDF document text
    • http://radiosalsa.fr/php/rs/filesupload/file/tapujaruwewotobefema.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613f5c6875f39---nupubufesitumogedofijibun.pdfIn PDF document text
    • https://amigo-shop.105h.net/upload/files/51734165854.pdfIn PDF document text
    • https://tvmreza.tv/ckfinder/userfiles/files/30617058360.pdfIn PDF document text
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/7831e68a52514a20c9237bc3b92d0744/busakiwokapix.pdfIn PDF document text
    • http://solyaris.pro/admin/ckfinder/userfiles/files/16855947050.pdfIn PDF document text
    • http://accessibilite-salle-eau.com/ckfinder/userfiles/files/neroxukudejejisudojen.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613df4aa7d0e0---jeziwujulikira.pdfIn PDF document text
    • http://metabolitplus.ru/files/file/1445116913.pdfIn PDF document text
    • https://easternresources.net/ckfinder/userfiles/files/52569951727.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=messenger+not+responding+androidPDF 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_off0000e299.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE299 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000faab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAAB 17860 bytes
SHA-256: e6701cb388c71393298867f399190ac654cba2e8f364604721c0d5f4748f2648
font_02_sfnt_off000128db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128DB 10516 bytes
SHA-256: 1d71eb359c39474ed09383dc0c70d133de86ce51fe9e4be1e858de00b38720de