Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9ff375f6a53b409…

MALICIOUS

PDF

80.6 KB Created: 2021-10-17 00:08:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 881a4ed77fbb86babfe8dbd305d52f3f SHA-1: 9ce69f17241455f556a2012c8f0857b9ad991142 SHA-256: d9ff375f6a53b4099a08435a709fa0446f863de62fb03a328d6e7bf67fcea2b2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that point to various websites, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of link farming on potentially untrusted domains. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://huntic.ru/uplcv?utm_term=best+websites+to+learn+english+for+free PDF link annotation
    • https://hotelgaric.com/upload/datoteke/38373598198.pdfIn PDF document text
    • http://sahamit.net/userfiles/file/vokuneri.pdfIn PDF document text
    • https://designmaster.in/scgtest/eec-new/codelibrary/ckeditor/ckfinder/userfiles/files/86189620004.pdfIn PDF document text
    • http://ff-engineering.com/userfiles/files/jelasowefomutitab.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614319444752d---71870003886.pdfIn PDF document text
    • http://rm-centr.ru/uploads/file/genun.pdfIn PDF document text
    • http://kleinschaden-expert.de/userfiles/file/31851079466.pdfIn PDF document text
    • http://abcgsgeds.friendship-match.com/upload/files/tilupagubaguxu.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16150fa422f265---7399831356.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131c1f48399a---vetirexoz.pdfIn PDF document text
    • https://amthanhanhsangchinhhang.vn/upload/files/bugapo.pdfIn PDF document text
    • http://szigmetal.hu/editor_up/8324341552.pdfIn PDF document text
    • https://artgallery.devctn.com/ckfinder/userfiles/files/rubab.pdfIn PDF document text
    • https://lesartsdansmonjardin.com/userfiles/file/20210922123112.pdfIn PDF document text
    • http://uptownherndon.com/uploads/files/xozew.pdfIn PDF document text
    • http://proximeo.com/ckfinder/userfiles/files/13322084036.pdfIn PDF document text
    • http://ankamet.com/userfiles/file/90880221689.pdfIn PDF document text
    • http://rszm88.com/upfolder/e/files/20211017013026.pdfIn PDF document text
    • https://rajakedua.com/contents/files/17589562784.pdfIn PDF document text
    • http://clairvoyantinfotech.com/demo/images/19973332512.pdfIn PDF document text
    • http://kahsport.cz/userfiles/file/lifif.pdfIn PDF document text
    • http://primethailand.com/ckfinder/userfiles/files/xenovujovuga.pdfIn PDF document text
    • http://smenergy.kr/uploaded/file/4849606446135bd78e1de7.pdfIn PDF document text
    • 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_off0000d6f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F6 10772 bytes
SHA-256: 573314bd33b2fdba70d70e4c8eb242ba9e869eab1c559c5a3bbebf44ef8cf5fe
font_01_sfnt_off0000efcd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFCD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000107df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107DF 17204 bytes
SHA-256: 0c32c67fcf9278909aa23c9dd20df9f1c5dcfdf9c949d0890a65c64d8cf831cd