Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdd713b206c3630a…

MALICIOUS

PDF

83.6 KB Created: 2021-09-22 16:11:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4dcd831e69f9d5cecd06a7f157244718 SHA-1: 8b7e77e5df42bc9eb34c13aaa85279581089fe8b SHA-256: cdd713b206c3630ae8d125a1c96b3915aee1f7481dbb767db3424b78395aa73c
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing or trojan variant. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. While no scripts were directly extracted, the nature of PDF exploits often involves JavaScript for redirection or payload delivery, hence the inclusion of T1059.007.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://argekaucuk.com/nbg/upload/files/sidonupurukebovujoz.pdf In PDF document text
    • http://bndweb.nl/upload/files/mojetet.pdfIn PDF document text
    • http://nexxstep.nl/userfiles/file/pazujifazirewirobulumiz.pdfIn PDF document text
    • http://diysmart.net/userfiles/file/jexizekiroxitev.pdfIn PDF document text
    • http://ominocoibaffi.it/userfiles/files/26888923342.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614137a227d8c---lupexuluxovizidisokitaw.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133cc9ac40cd---fapofojus.pdfIn PDF document text
    • http://e-pisanie-prac.pl/famprojekt_z_serwera/images/file/20459418685.pdfIn PDF document text
    • http://niszczeniewaw.pl/userfiles/file/73131555843.pdfIn PDF document text
    • https://n-zvuk.ru/upload/file/rezepezedifibetineli.pdfIn PDF document text
    • http://bakersfield.thepokeluau.com/uploads/files/nofoxomukakeguput.pdfIn PDF document text
    • http://stl-hk.net/userfiles/21015351562.pdfIn PDF document text
    • https://hardlineconstruct.ro/app/webroot/files/userfiles/files/wofakivom.pdfIn PDF document text
    • http://diegogenna.it/userfiles/files/petitawowebafurutuditamex.pdfIn PDF document text
    • http://vatlieubaooncachnhiet.com/userfiles/file/70923638974.pdfIn PDF document text
    • http://teewer.mn/ckfinder/userfiles/files/lobeg.pdfIn PDF document text
    • https://saint-florentin.charcutier-traiteur.fr/ckfinder/userfiles/files/dusosolekurusetabinoda.pdfIn PDF document text
    • http://smartdeal.pl/files/upload/files/12721509387.pdfIn PDF document text
    • http://anthonyjcincottalaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/42970017262.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7f0eb872d---negototebojoxofubage.pdfIn PDF document text
    • http://wenyanchem.com/upload/files/kibasawotabarog.pdfIn PDF document text
    • http://phrabat.net/UserFiles/File/torezepazevosubekupuz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=demon+slayer+watch+online+english+subtitlesPDF 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_off0000e276.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE276 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fa8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA8D 11120 bytes
SHA-256: 0cb6dc7c1a8528363ed5a39828e83e5e8d2fd8a4b7a4bbcdbd91b8d098f3d800
font_02_sfnt_off00011461.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11461 16884 bytes
SHA-256: 1e9ccc57507f2e87790226ea8adb10f51bf551da68db47805815bb76504718dd