Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef552ae5f7f05b86…

MALICIOUS

PDF

76.5 KB Created: 2021-06-29 11:49:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5d3dad3e37582d23febabb3312eb10c2 SHA-1: 11299055eba5a3c6a91e4a4d449ef860aaf47d26 SHA-256: ef552ae5f7f05b86d5aee035fe7998695f35791c344782ec115f545f1649acd5
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. The heuristics reveal it functions as a link farm, pointing to numerous compromised WordPress upload directories and disposable hosting sites. While no scripts were explicitly extracted, the nature of the link farm suggests it is designed to lure users to phishing or malware-hosting sites, aligning with the 'Spearphishing Attachment' technique.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://seventyfirstclassof69.com/clients/60772/File/73641978791.pdf
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/16074c0c81a426---55813976349.pdf
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/160ac50801f331---wegudevozenoxe.pdf
    • https://landi-bg.com/images/file/kulixorosovirijokisevi.pdf
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/bdb359a1fc9deca146257a4b1fe3edfb/20949402848.pdf
    • https://arnetbilgisayar.com/upload/ckfinder/files/tululizuwimisudezekidetu.pdf
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/ab0892437d218805d107af1fe50bbfe3/70614362427.pdf
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/9c37669d4b6fa1c0102dbda5015688ba/mesivatorewefilamife.pdf
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/5tqu3dtakflqeqpn6v4he6n1r6/tagosinaku.pdf
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/mfengldvnf3nl3jq43j17dli05/7902375897.pdf
    • https://cr2tek.com/userfiles/Proj_Name//files/gunasidagijakosagosavo.pdf
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/16089f643cab16---turilanibeza.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1606d1a72ad285---zufilasuvoju.pdf
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160863a7c7ebaa---videvamosaso.pdf
    • https://www.sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a9f14ac3fed---jiturojegeturaxebufalawi.pdf
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/05166e29e1e56bf65524cc77dc27edf7/putofunosasorason.pdf
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609879f4a60c3---87857806668.pdf
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//39360095613.pdf
    • http://www.deco-interieure.com/userfiles/file/nukopogad.pdf
    • http://bigdoughpizza.com/uploads/files/95260283535.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/904jus4e4ugpcc8v369cfnb8o0/46782791841.pdf
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/zunexojojaj.pdf
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16078156b2df80---60827885137.pdf
    • http://polimak.pl/userfiles/file/nunujifidamigufomilanaw.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=our+lady+of+the+angelus
    • 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_off0000c74a.bin
f797f78675087b3b978797cbdc427b38a63b2a5fc98054f1b87d95e7bcd918e4
pdf-font-stream PDF embedded font (sfnt) at offset 0xC74A 17184 bytes
font_01_sfnt_off0000f421.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF421 16792 bytes
font_02_sfnt_off00010c38.bin
6757d0d0fd79b0965b0c4ef7157fc42590f1673ca4e732ebde8e5ab1089e8def
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C38 10780 bytes