Malicious PDF — malware analysis report

Static analysis result for SHA-256 a54cb8597b49ac6a…

MALICIOUS

PDF

81.9 KB Created: 2021-09-18 12:44:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e86566ef9d608f1eccff3c3a38db478e SHA-1: 987d2266a3758be7e36f3b24b41367e58c3df173 SHA-256: a54cb8597b49ac6a9237c73680f4a15b9192f5802f6e2b2bb9e4ceaa59c1b58d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, suggesting a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly indicate malicious intent. While no scripts were explicitly extracted, the nature of the URLs and the 'link farm' heuristics point towards an attempt to redirect users to malicious sites, potentially for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://queure.ru/uplcv?utm_term=create+apk+from+url PDF link annotation
    • http://umhouses.com/uploads/files/10490612823.pdfIn PDF document text
    • http://hermandadperdon.es/userfiles/file/palekokigag.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/7dv4n2lf4kk9qktki2ii6oarli/lamufivexodisuwasajedo.pdfIn PDF document text
    • http://itnetworkconsultingsf.com/helpdesk/app/webroot/img/userfiles/files/witivosoxanuxusijutixobip.pdfIn PDF document text
    • https://birotex.rs/images/files/peveropemer.pdfIn PDF document text
    • https://ntiverification.com/userfiles/file/dufonogurobolimanove.pdfIn PDF document text
    • http://bassonconsulting.mc/userfiles/file/weban.pdfIn PDF document text
    • https://www.bosingels.nl/ckfinder/userfiles/files/33498363681.pdfIn PDF document text
    • http://wksx.top/images/userfiles/file/47023590692.pdfIn PDF document text
    • http://mvpbuilding.com/userfiles/file/95947138336.pdfIn PDF document text
    • http://zae.me/datafiles/file/76710641201.pdfIn PDF document text
    • https://absoluteanytime.com/media_file/files/files/94678175517.pdfIn PDF document text
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/d599ee5f8c69ebaea36d61b6fc158201/69116615175.pdfIn PDF document text
    • http://antonellascarpittadesigner.it/userfiles/files/ruvulebavibesadegoroba.pdfIn PDF document text
    • http://uekekb.ru/!upload/files/rovojuf.pdfIn PDF document text
    • http://sushistoryus.com/uploads/files/53139295305.pdfIn PDF document text
    • http://2015.letnifestiwal.pl/ckfinder/userfiles/files/jamifixepodilijazifafu.pdfIn PDF document text
    • http://www.nachtruhe.info/up/files/55970737694.pdfIn PDF document text
    • http://dekobonner.de/userfiles/file/zuzifajef.pdfIn PDF document text
    • http://chugguwang.com/files/fckeditor/file/miwafufenekidizipoda.pdfIn PDF document text
    • https://www.vasutaszeneiskola.hu/ckfinder/userfiles/files/58995467634.pdfIn PDF document text
    • http://phdpecs.hu/userfiles/files/sugetamikimupusuba.pdfIn PDF document text
    • http://csim.jp/ckeditor/uploads/files/95898115863.pdfIn PDF document text
    • http://kursverwaltung.fit-n-essen.ch/ckfinder/userfiles/files/32417031507.pdfIn PDF document text
    • https://blgjad.com/upload/files/50026913795.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130b2fa3fea7---79977376034.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d77c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD77C 18780 bytes
SHA-256: abf3c993f7618762e4ec3895ecfed76132d2d25411518d4d56b68948661c4a66
font_01_sfnt_off000108bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000120d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120D3 10380 bytes
SHA-256: f1b3a44d2f3e4adeaa2bb560a68da28663acf554c8b9a486abb5e1278b8732d8