Malicious PDF — malware analysis report

Static analysis result for SHA-256 b946223a4bfb02f7…

MALICIOUS

PDF

86.9 KB Created: 2021-08-04 00:37:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c9fe1253d85c7187c3f06bf7a5ee847e SHA-1: e4b693b4ec1c7fe23a36a3ebf3edecb631d36ebb SHA-256: b946223a4bfb02f7c643c350f317775b8bc263f7eac0cd706629f7fb12a52a8b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised WordPress sites and disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. The presence of multiple external URIs and link farm heuristics confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://coretry.ru/uplcv?utm_term=magnetism+and+electricity+word+search+worksheet+answers
    • http://dabaizhongxue.com/upload_fck/file/2021-5-21/20210521191016901585.pdf
    • http://axwelindia.com/uploads/zimivebolako.pdf
    • http://omatsuri.kr/data/userfiles/files/89392671583.pdf
    • https://aronabritcan.com/userfiles/file/lepisubojamurokegej.pdf
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16090f2198f8f8---wewabag.pdf
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/06046b54ea2f41606f8ddd278d342420/juxalokubebumewaxufesox.pdf
    • https://altonika.pro/files/fck/file/75906689422.pdf
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/1a2f77f46867723dab4fa760d3852d22/33593556986.pdf
    • http://sofia-es.tokyo/yamituki-n/uploads/files/84622656546.pdf
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb454730d3---15927156524.pdf
    • http://ultraljud.nu/bild/files/7259607161.pdf
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/bc180d06d80bf5e25924cd4d956a3920/gasutaburufa.pdf
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/0c88cf4df54e8d87ed561dde46b9eb15/1774512218.pdf
    • https://magatek.com/documents/file/33344249637.pdf
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/6852ff2b7f0be8f132860ec8466e33ba/narakise.pdf
    • http://bridgestone-ice-cruiser-7000.ru/ckfinder/userfiles/files/xejadagobafe.pdf
    • https://lasvegasrebath.com/wp-content/plugins/super-forms/uploads/php/files/520b7d47c3a10c7b0c4d2a9b50b13bec/65377574698.pdf
    • http://cricalliance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074975e0bd6b---91047712883.pdf
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/16107a6d154630---22421691267.pdf
    • https://burmesecatclub.nz/wp-content/plugins/super-forms/uploads/php/files/ecb643469c96fcf36eb50355be0bbc46/giduwa.pdf
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/23303804c4d9a74626d98b4d65a239e4/lexerepixevenufa.pdf
    • https://yingzhaoliuart.com/upload/file/70013604215.pdf
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/u56s4m3s3v25g3mhkp7oprat32/sewiruvijepazaporomelela.pdf
    • http://alituncer.com/userfiles/file/57756706999.pdf
    • http://anhbanglaw.com/userfiles/file/78588113233.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_off0000ef97.bin
d6e694a51c14317f253fc60d9b0658fd85067224d270b8fead9ba7700fbcc5f2
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF97 16896 bytes
font_01_sfnt_off00011bc7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BC7 16792 bytes
font_02_sfnt_off000133de.bin
686593f6c3b10348581d1f6f2070402dd078193681d1b2e5911f3a07553f0d50
pdf-font-stream PDF embedded font (sfnt) at offset 0x133DE 11104 bytes