Malicious PDF — malware analysis report

Static analysis result for SHA-256 c53953f23ed2fb31…

MALICIOUS

PDF

143.3 KB Created: 2021-06-25 17:57:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 81e85b916cd3f3340b450b7a8d23ef20 SHA-1: ed3ca162d8ad8049773c79b6dc3a9e46ab5e283b SHA-256: c53953f23ed2fb31a879bea3da27a9c3247c15faa4f6609e9790d448c2f0809e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised WordPress sites, likely serving as a distribution point for malicious content. No scripts were extracted, but the structure suggests an attempt to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

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 http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608802051e1f6---wopimedojidosijekexereme.pdf
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/hi1sqehv5rlm82cq8erea2pfe3/xosufisofodekigi.pdf
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b01a9b0db36---73023551334.pdf
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/7c134cf433f90f4f8156ed83576b71fe/85127605906.pdf
    • https://summit-christian-academy.org/scauserfiles/files/80478251724.pdf
    • http://healthywithhart.com/res/file/30668763684.pdf
    • https://hpsoft.shop/upload/files/nupifevogegogowujuxomemun.pdf
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607e5c2166643---33886991515.pdf
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/6f8dc49d47cc8e8ee5b6bdf2b125b669/nisudamanasagetagudojure.pdf
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/71645debad4e243fcd58d9c1e4eff13c/13369677918.pdf
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/8d5c45db8ce55a8fd3529d5b66b5c541/mavedafolafezigurebafijof.pdf
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/2f6122d00dce2f07b45367b2268d775c/10608509661.pdf
    • https://erinmillssmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/j9lqp7g3saafkdpbc8mhek6v66/rukowaxosanasinaniwovefer.pdf
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071457664dee---sijenasutagureni.pdf
    • http://novichiha.ru/pic/file/39070264496.pdf
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1609464c233389---39540040218.pdf
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/160726a4f6a3e8---tawazaluzepowuju.pdf
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095cc5eb4318---31261495510.pdf
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b28e2809e9d---xudaforadekinesezezob.pdf
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/fe362568c27130299c35f776f68b6d8c/88931807329.pdf
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609a0d6a0a7e1---20519182502.pdf
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d35a63ec2---87348982805.pdf
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/0f6641caa141dd0ae9b16efa39c03417/xorigotosono.pdf
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160942f595f801---80630154584.pdf
    • http://incucinaconalberta.com/userfiles/files/83256684439.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=a+new+hope+han+solo
    • 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_off0001ce52.bin
e2e6a9e8f1ef916772e2e87a40ce2b2da828032d148fa7b78f562f589e257347
pdf-font-stream PDF embedded font (sfnt) at offset 0x1CE52 10128 bytes
font_01_sfnt_off0001e4f8.bin
7738c518403ec2290462f392c5c67385261f85d09b8b45475f8c40250192f5a5
pdf-font-stream PDF embedded font (sfnt) at offset 0x1E4F8 19312 bytes
font_02_sfnt_off0002160c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x2160C 16792 bytes