Malicious PDF — malware analysis report

Static analysis result for SHA-256 9fa6840ffd984f07…

MALICIOUS

PDF

87.9 KB Created: 2021-09-09 15:12:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 4fce5b787646d40c0ef3ad18dab36c28 SHA-1: de104aee3251068d3639d78a5a62aae5fc17f127 SHA-256: 9fa6840ffd984f072158e18d5e9f09114d7a62fb79066eb6edcc1b21fb4adc2d
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to potentially compromised or disposable hosting. The document body is heavily obfuscated and appears to be non-readable content, further suggesting a malicious purpose rather than legitimate document content.

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 http://studiocastigli.eu/userfiles/files/dovetixomijomuzafalu.pdf In PDF document text
    • http://tochuchoinghi.org/files/3147026025.pdfIn PDF document text
    • http://chixue.com/uploadfile/file/20210906134713.pdfIn PDF document text
    • http://myphamlulanjina.com/upload/files/gupipevajonosobatisozep.pdfIn PDF document text
    • http://hoangnamjsc.com/upload/files/86997380345.pdfIn PDF document text
    • http://mezon.jp/userfiles/file/4394571948.pdfIn PDF document text
    • http://hanakspotrebice.cz/eshop/ckfinder/userfiles/files/19198716154.pdfIn PDF document text
    • https://hopadive.cz/ckfinder/userfiles/files/21940810881.pdfIn PDF document text
    • http://valentine.tutaylamhet.com/storage/ckfinder/files/bebadagal.pdfIn PDF document text
    • https://ajambary.com/userfiles/file/99888376948.pdfIn PDF document text
    • https://rewaqousha.net/userfiles/files/95254244954.pdfIn PDF document text
    • http://www.tm-africa.com/beta/public/uploads/cms_filescms_files/lukarozizutol.pdfIn PDF document text
    • https://upbfassadenbau.com/upload/file/24054027065.pdfIn PDF document text
    • http://primebrokeragetx.com/ckfinder/userfiles/files/xinizawomovuxinoni.pdfIn PDF document text
    • https://fratellifurloni.it/file/70130526994.pdfIn PDF document text
    • http://jjmcp.jp/userfiles/Image/file/29867010586.pdfIn PDF document text
    • http://churchtextile.com/userfiles/file/49917487454.pdfIn PDF document text
    • https://gkia.org/kingkong/userfiles/files/30798551994.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/62756904183.pdfIn PDF document text
    • https://ww150007.linebot.net/upfile/files/20210903064613.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f76ad0f055---zelodipezefesafozavur.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/161336aac0dbf5---vivozaroloderedalobanew.pdfIn PDF document text
    • https://kungfuclasshongkong.com/louis/taichi/ckfinder/userfiles/files/3257319298.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/df53f9e92af7f1332aea678d9069a4aa/bikenikiwerexamira.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16130867a481f9---88063657718.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=chasing+cassandra+read+online+freePDF link annotation
    • 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_off0000f0dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0DD 18676 bytes
SHA-256: e2074d495e38173b4bee38070694af05a69885ce02f876ca92097800f2b3f10d
font_01_sfnt_off0001212b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1212B 10688 bytes
SHA-256: 1b37084e8571602fe98c6d0f0898a8ca68a2da4900c8b7f08328418a7622b33a
font_02_sfnt_off00013965.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13965 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1