Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b39dc684b6b6926…

MALICIOUS

PDF

75.0 KB Created: 2021-09-06 05:51:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 4a52a01bdd756fdf50e2675df4f32846 SHA-1: cf1c55b3014f12fdf2b14d915987f3f90dae7449 SHA-256: 6b39dc684b6b69260654c3f5684d1f4308557a48217829572441cfe209d59e64
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised CMS uploads or disposable hosting, suggesting a phishing or malware distribution scheme. The document body was unreadable, but the presence of numerous external links strongly supports the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/fh68lv9kqptlqv30pk8qrhfg10/funupogik.pdf In PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cd7a7eba1ee---wugesujoniselawatav.pdfIn PDF document text
    • http://kashima.cc/userfiles/file/podoxofofilutofineriziwe.pdfIn PDF document text
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/bti87hsqbc2b1e6sds9jdcacq4/kidotubuxededajatenozalur.pdfIn PDF document text
    • http://vitaminyplus.eu/files/file/nopebepositorofiwebulade.pdfIn PDF document text
    • http://ingfrimale.com/userfiles/files/garovofugavibu.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1607bead1d2afd---sevajowiduduzerigeneva.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160f99986f2ef3---44176655228.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608789b0ba6dc---33425038850.pdfIn PDF document text
    • https://ildiko-szepsegszalon.hu/userfiles/file/44720137194.pdfIn PDF document text
    • http://thuonghieutoancau.vn/uploads/files/52389811536.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/10ac846c96f8eb1d2271babec13998a7/wasogukamojed.pdfIn PDF document text
    • http://spy-military-labs.com/userfiles/file/25311891593.pdfIn PDF document text
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/92578ca8ef68582fde18c2e9cfb62844/5740643890.pdfIn PDF document text
    • https://xn--bren-mgenwil-gcbf.ch/sites/default/files/fck-uploads/file/27788624835.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/6a36308a9f05fab0077f832515540774/difazifu.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0e73c3d253---25083790310.pdfIn PDF document text
    • https://2acontractor.it/images/file/jafitopogajisisebu.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078f778301af---95882378063.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/v7qrtp7s28kct9qvq82a4opjju/rajiwewesizaditazosis.pdfIn PDF document text
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/tits8b9u82jgoe7m512v7hh542/36943009972.pdfIn PDF document text
    • https://ntct.dz/ckfinder/userfiles/files/pujonitinidiwagokov.pdfIn PDF document text
    • https://permargi.com/files/galeria/files/7585975138.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=apeman+a79+manualPDF 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_off0000bdf5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDF5 18968 bytes
SHA-256: d265a009b1fa7436b14074cc93400ffb6fc039cc56a1ef1b6cd94fe598b57d55
font_01_sfnt_off0000ee38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE38 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001064f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1064F 10136 bytes
SHA-256: 043f25722c622f95e3989eacb8b4a27f60b2dda27d94da05e2a289775fecb594