Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6fb3f20e97aa861…

MALICIOUS

PDF

84.7 KB Created: 2021-09-17 22:48:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: d69d302513c42f1e7555e8e347bf09d7 SHA-1: 19375833db652483f505d358aab1785ffcda45ac SHA-256: a6fb3f20e97aa861def951d8cd4d0d79806357031e64300beb99f2073526e832
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to potentially compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the nature of the document as a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://kvkumariajnkvv.org/singhania/downloads/file/kobejivegibikolurenunuj.pdf In PDF document text
    • http://jiachuankeji.com/upload_fck/file/2021-9-16/20210916122233437820.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/6022295754.pdfIn PDF document text
    • http://santeh.md/img/files/mumoxiben.pdfIn PDF document text
    • https://uudanbury.life/files/file/53183342029.pdfIn PDF document text
    • http://exclusivelimoservice.com/ckfinder/userfiles/files/muvolebobugisaba.pdfIn PDF document text
    • https://montpellier-business-plan.com/mbp/upload/images/images/upload/ckfinder/95959163813.pdfIn PDF document text
    • http://msmzizkov.cz/data/dokumenty/bovevurowanijegijozobaw.pdfIn PDF document text
    • http://musikpark-live.de/userfiles/file/zexibikowoza.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/xorasivovuvupelod.pdfIn PDF document text
    • http://lube-stc.com/ckfinder/userfiles/files/zogezimiwizasel.pdfIn PDF document text
    • http://library.nesdb.go.th/ic/admin/ckfinder/userfiles/files/nisiripuxarupotu.pdfIn PDF document text
    • https://oncetrabzon.com/resimler/files/fivexaxuxevetu.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/zerimaferabu.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613034395330a---xixakugizexeza.pdfIn PDF document text
    • https://relans-nn.ru/images/docs/file/728615412.pdfIn PDF document text
    • http://ghibms.com/userfiles/files/zenilumite.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613de2997b2bd---fubemifukipoduvu.pdfIn PDF document text
    • http://werder-ritter.de/UserFiles/File/82675939908.pdfIn PDF document text
    • http://acpiindia.com/userfiles/file/55371568784.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/df1d665218766b4d9fb1d01757afb072/tetukalo.pdfIn PDF document text
    • http://roberlo.cz/www/files/file/85854983206.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210911212506934.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=friday+night+funkin+week+7+free+to+playPDF 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_off0000e0d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0D1 11028 bytes
SHA-256: 6013e9caed13a76b49e6b25ba12816960552831b9ec2af7739b11b8455ce0ae4
font_01_sfnt_off0000fa42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA42 19064 bytes
SHA-256: e93f5fc9d581b63e8aaa6a1d880d4787885cc9e2a3cffa1cb409ce8719bad70d
font_02_sfnt_off00012be4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1