Malicious PDF — malware analysis report

Static analysis result for SHA-256 54f1af9f4a28bafd…

MALICIOUS

PDF

96.7 KB Created: 2021-07-04 05:41:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f37be10e13a1971978d438fe961046f2 SHA-1: bca68cac0c9c9ce48a7599259c65b8763b4b747b SHA-256: 54f1af9f4a28bafdf1df0c4e071031acdaf230fae7c0d4d91fd31af22863b22e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL structure and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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 https://bleikss.com/userfiles/file/pesosuwoxulasod.pdf
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/119b0f7e5b8cbc5a50ebe2a665b1f32c/14464309105.pdf
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160adcfe0c79a0---75239435393.pdf
    • https://dutchfansitenetwork.nl/ckfinder/userfiles/files/wudinizapexutiravuxusi.pdf
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3c4ac661b---84488454040.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160c31efb61820---47535443557.pdf
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160803471eff73---tugiveboril.pdf
    • https://georgiamusicpartners.org/wp-content/plugins/super-forms/uploads/php/files/cb943db6bffec3551328c858f546601a/78016681682.pdf
    • https://vasantviharproperties.com/userfiles/file/44940158699.pdf
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/5e7op3cfj80m3q048dopelfabv/58751390909.pdf
    • http://dienmaybaongoc.com/ckfinder/userfiles/files/35228374100.pdf
    • http://bakoca.hu/files/file/65729642163.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609babbdefa0c---65024341004.pdf
    • http://ehoron21.mn/uploads/files/50812795481.pdf
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/0923597ab505f975ae6bd3963b8054ba/xedow.pdf
    • https://szekszardportal.hu/userfiles/file/56511274091.pdf
    • https://prosaison.fr/userfiles/files/zewumokogeju.pdf
    • https://navliecky.net/userfiles/file/91328815491.pdf
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/ccjqm8apc2aundcs6506mbqarg/15590808076.pdf
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609f71da747b1---pesemalanixifiko.pdf
    • https://arch.ua/ckfinder/userfiles/files/83996930038.pdf
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f0227b1932---lituz.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=new+pacemaker+2020
    • 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_off00011a55.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A55 16792 bytes
font_01_sfnt_off0001326c.bin
2a5cde254f53df987bc1a86d2ad212ea5732ca858ebfcb23e1ab45e9a4ea650b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1326C 10304 bytes
font_02_sfnt_off000149c6.bin
464cc7269184d416cca689ab82bc25a6c083c1a6305e1ca23418b649fec1b514
pdf-font-stream PDF embedded font (sfnt) at offset 0x149C6 17020 bytes