Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1f6b6b67d28b777…

MALICIOUS

PDF

69.9 KB Created: 2021-09-26 01:36:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 68493089be88d1e4119d827e089d2b58 SHA-1: 1329661d940522c23de52a6371aa5c692be6f0a0 SHA-256: a1f6b6b67d28b77709d3312cd129e2eccf833a71a2fa961e427cb7b79d957dd1
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, suggesting a phishing or malicious redirection scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing campaigns that leverage link farms to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://asijskepotraviny.cz/files/file/97176782510.pdf In PDF document text
    • http://millecolori.it/images/file/35536489391.pdfIn PDF document text
    • http://www.ccengis.be/applications/ckeditor/addons/ckeditor/ckfinder/userfiles/files/60160705471.pdfIn PDF document text
    • https://sharjahcements.com/images/bulk_images/files/92476614175.pdfIn PDF document text
    • http://el-system.jp/uploads/2012/files/703848315.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614f2d25979c2---jezukivinubemamobikaf.pdfIn PDF document text
    • http://maymaygiaydachidang.com/upload/files/vanemepijoravo.pdfIn PDF document text
    • https://officialbacknumber.com/editor_up/voxixebajal.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cc3304580b---59906002596.pdfIn PDF document text
    • https://mdteam.se/ckfinder/userfiles/files/78702615892.pdfIn PDF document text
    • https://medtek.vn/storage/file/xudedamidapivuj.pdfIn PDF document text
    • https://casabresciani.it/uploads/file/kanenuxodabefe.pdfIn PDF document text
    • https://www.zolmedis.lt/ckfinder/userfiles/files/xofukojilipeva.pdfIn PDF document text
    • http://ventmetal.ru/userfiles/files/44169080543.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/bsacpeot4c84glt8kdv5cltrim/7553491601.pdfIn PDF document text
    • http://www.cbs-emballages.com/upload/file/17838687084.pdfIn PDF document text
    • http://olgapolyakova.com/files/files/bobibejumomakut.pdfIn PDF document text
    • http://ventilatoryzlin.cz/images/file/nupoxavorexuvug.pdfIn PDF document text
    • https://frisch.ro/files/file/21268369786.pdfIn PDF document text
    • https://tradegateindia.com/userfiles/file/70619262593.pdfIn PDF document text
    • http://kimwendelldesign.com/ckfinder/userfiles/files/penewisonunazozipazax.pdfIn PDF document text
    • http://talleresjpg.es/img/file/likepeluwamasorizizax.pdfIn PDF document text
    • http://club-integra.ru/userfiles/file/812803167.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=minecraft+what+to+doPDF 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_off0000b194.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB194 16172 bytes
SHA-256: 3570926f0a53727acdcda109ba53e573873049119110060a93a285285d424311
font_01_sfnt_off0000da78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA78 10436 bytes
SHA-256: 707f5ebb2f2ff2ef67da90b879a0fbdb2a49b461e713147e2d4e0b1ed627a26a
font_02_sfnt_off0000f227.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF227 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1