Malicious PDF — malware analysis report

Static analysis result for SHA-256 0b6b10c19522acea…

MALICIOUS

PDF

74.3 KB Created: 2021-09-16 19:27:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0392b92dc83c07cc2839ac7ecafae06f SHA-1: 6626d41f680f5bf040b5676a4d1316f8ab01a097 SHA-256: 0b6b10c19522aceab9f2513e8023d0dbd60acce76b411b1f86e1b50c1459a619
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and link farms pointing to potentially compromised websites, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking clear user-facing text but containing embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://cructi.ru/uplcv?utm_term=english+persian+dictionary+app
    • http://kanoonkaraj.ir/dbmanager/filebank/htmlgallery/file///92406953497.pdf
    • https://ises.smithpressautomation.com/phpsites/vertical_living/uploads/file/98895083369.pdf
    • http://cu-hinothai.com/ckfinder/userfiles/files/dagoruluxolewexidif.pdf
    • http://tofuyatogo.com/uploads/files/ludoxawupawimemutu.pdf
    • http://studiofagiani.eu/userfiles/files/jibivakametot.pdf
    • http://cjatkinson.com/userimages/nujetitesaxirariripafefip.pdf
    • http://fosterfreezesantarosa.com/uploads/files/sepototorafodosikedileto.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132cfc15fc13---nezuviloxexolemiburigolu.pdf
    • http://bebelino.ru/userfiles/file/85807382769.pdf
    • http://skkouty.cz/ckfinder/userfiles/files/95766648383.pdf
    • https://sabunwangi.com/contents/files/nanovog.pdf
    • http://pc-driver.ru/userfiles/files/53983981725.pdf
    • http://zap-interactive.com/uploads/files/fivebulisikoverimi.pdf
    • http://zagazzo.com/userfiles/file/12346680254.pdf
    • http://innovad-ltd.com/userfiles/file/kubajetaju.pdf
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e1705b1db1---8435212143.pdf
    • http://taemyung.com/data/upload/file/sibubetigemokoliledi.pdf
    • http://crabandclaw.com/uploads/files/verimotokamipojibijaxi.pdf
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613519970b76a---vuzuluro.pdf
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/c2d5e1e60b901f00721a9ed9fe281134/71186078825.pdf
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/70d6d1509ac3eada0b40f5edda710908/lamofowimodegavuwinepiv.pdf
    • https://b7b.reviewz.eu/app/webroot/files/userfiles/files/7310702846.pdf
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/dbc2d06496bd8ad877b0defe73d4e8f6/ziletagabopapifewulavapok.pdf
    • http://baby-daycare.com/uploads/files/202109030757349124.pdf
    • http://www.slenderclub.cz/ckfinder/userfiles/files/9835180021.pdf
    • 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_off0000be22.bin
a7a267736a10f44711dcdec50b4f32a377bf78dd3c88f817d3a5d640c9b46f52
pdf-font-stream PDF embedded font (sfnt) at offset 0xBE22 17052 bytes
font_01_sfnt_off0000eac2.bin
0b31c222b961aac396ebf0af45b8e699e96699ea87621a6c2fb6d8ed92295dbc
pdf-font-stream PDF embedded font (sfnt) at offset 0xEAC2 10892 bytes
font_02_sfnt_off000103af.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x103AF 16792 bytes