Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c623fa8a1a8d77f…

MALICIOUS

PDF

84.9 KB Created: 2021-06-27 16:06:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 57f5769f5cd5870d4799efdb5d02c0e7 SHA-1: 05b15d9cb03902514709f34412a4ce0c76124607 SHA-256: 4c623fa8a1a8d77fdf5b1c7610a31da3666e9398945b17bf1ad59df0ce06426d
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to websites that appear to be compromised CMS uploads, indicating a link farm or redirection scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or distributing further malware. The presence of multiple distinct hosts and the use of 'utm_term' parameters suggest an attempt to manipulate search engine results or direct traffic to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160724ec939018---5798543434.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a443b866982---86027303760.pdf
    • http://jinistudy.com/_UploadFile/Images/file/44554727546.pdf
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/343e0a5be75df125c41af304809f41d8/63540885744.pdf
    • http://csptech.net/admin/userfiles/file/bisirevixisitapoposo.pdf
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093226b7e5b8---soxevezemejujenori.pdf
    • http://ateliergermain.net/sites/default/files/file/pefolakatiruxotokilex.pdf
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093e5965e7c7---wizegiv.pdf
    • https://arte-salon.ru/upload_picture/64515240212.pdf
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/7e722bb47df49070070d7f47361f8876/64321332868.pdf
    • https://www.federatedlighting.com/wp-content/plugins/super-forms/uploads/php/files/9fabf526906a1d4dbefc84d045b7f8bc/xexuxarojofo.pdf
    • http://caratow.eu/userfiles/file/55741351086.pdf
    • https://pet-fashion.ro/mm/file/20552655083.pdf
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/b800542693b307b281359d0a7cae1e86/25606021997.pdf
    • https://www.westcountrystoves.co.uk/wp-content/plugins/super-forms/uploads/php/files/fa14af02989d0e42c2569035b90b1a2d/mulusuwilezafepidag.pdf
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/tqmhimcpnpv6i84bu06hd74j6o/12397202212.pdf
    • https://omomediacion.com/wp-content/plugins/super-forms/uploads/php/files/2e389e2f028d328b75d1b0add6c11829/subew.pdf
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609af1b72f44d---lexotakegozosefaxi.pdf
    • http://asavn.vn/uploads/userfiles/files/77223276570.pdf
    • http://c-six.it/userfiles/files/90344521669.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5aeaa54cc---sulalupefikirokokululup.pdf
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1606d4ae362d71---15870094820.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=best+gps+coordinates+app+for+android
    • 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_off0000ea20.bin
12e9c0bc3bf80bb9ab0cb2f5d17b4535603effd1d4e79be31a245ad7282d9000
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA20 10804 bytes
font_01_sfnt_off000102fd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x102FD 16792 bytes
font_02_sfnt_off00011b0f.bin
3a210fa40db79dee4d538b2eda9c29901e9878942170e032480c860a12373f70
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B0F 16808 bytes