Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef8c91c2d3371f27…

MALICIOUS

PDF

81.4 KB Created: 2021-08-01 16:36:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2de482543ee5666ada63ebf2c19d2aba SHA-1: 5d06d21901b445b289bc87f836697af965dc5913 SHA-256: ef8c91c2d3371f27bec1701cbdbc68a1ed268b1e209d8ccecf0e79e89eb407f6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple compromised WordPress sites and disposable hosting domains, likely for phishing or malware distribution. The embedded URLs and the structure of the PDF suggest it is designed to exploit user trust and lead them to malicious content.

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://queure.ru/uplcv?utm_term=why+is+my+tv+aerial+not+picking+up+bbc+channels
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/d55d216b7b6fe5251a7c3937b0895f42/39662175445.pdf
    • http://smartpaintingplus.com/userfiles/files/18694472093.pdf
    • http://kaies.cn/upfiles/file/62567978898.pdf
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608648475475e---ruxelapefesi.pdf
    • http://originalbau.hu/imagesfiles/jiwiwuvafozezaj.pdf
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/9ea2d28d3e183b2aa204a4ad86228168/47022971646.pdf
    • https://getadoc.in/ckfinder/userfiles/files/vebutiperapozixiti.pdf
    • http://knuhpharm.kr/userfiles/file/20210714160750.pdf
    • http://superfasttv.com/uploads/files/podofufonikoratafolozobaw.pdf
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/799b59f315e83eb7f0290eca05e47df8/kopukine.pdf
    • http://bendhorseride.com/userfiles/file/95081916643.pdf
    • http://minhanh.com/files/78055150652.pdf
    • http://wienbildarchiv.com/upload_files/files/12277549794.pdf
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/160733a296e3d7---81293410588.pdf
    • https://clickkedai.com/userfiles/file/44555209323.pdf
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/d6efd2a62b67b3dde1ed850fb592914f/fowulelofexulupubax.pdf
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/65e0cad478dfd27e6f9caf31f87f177f/latimiwigewus.pdf
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/160cb9b4fabdde---33258638256.pdf
    • http://kimwendelldesign.com/ckfinder/userfiles/files/58621423460.pdf
    • http://denge.aero/upload/files/70625421569.pdf
    • http://accronline.com/userfiles/file/mavagam.pdf
    • https://tannhatviet.vn/upload/files/94442377604.pdf
    • https://www.posluh.hr/ckfinder/userfiles/files/31099113171.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d8ad.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8AD 16792 bytes
font_01_sfnt_off0000f0bf.bin
b17332d2dfcdfd5e24c352dbbcd7ab10a5b40e122804e403cdac07c8a5c94499
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0BF 17068 bytes
font_02_sfnt_off00011d91.bin
d4ca543175d873a8ddf61816928848c6e0455d88232b8dfefa8a4d85480b6595
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D91 11328 bytes