Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b71541df2fe3935…

MALICIOUS

PDF

82.2 KB Created: 2021-09-17 21:56:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 10e237f3ea87a00291803b047738e209 SHA-1: 3d2407877cf54c237c448d6f17a8c640a364dc88 SHA-256: 1b71541df2fe3935971c96be15c1c6d8efc40e840597e8b3092a447f306062fd
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of link farms designed to obscure the final destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. The presence of a URL with 'keylogger' in the UTM parameters suggests a focus on credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://huntic.ru/uplcv?utm_term=free+undetectable+keylogger+remote+install+android PDF link annotation
    • http://popnmusic.fr/userfiles/file/98535360188.pdfIn PDF document text
    • http://ubytovna-krumlov.cz/userfiles/file/78101751272.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612e9f736ab49---10011851530.pdfIn PDF document text
    • http://life-homeshop.com/asset/uploads/files/82956782712.pdfIn PDF document text
    • https://traveletrust.com/basefile/traveletrustcom/files/fidiwimogesisupolezivez.pdfIn PDF document text
    • http://www.extramas.com/userfiles/files/41150101883.pdfIn PDF document text
    • https://villadorottya.hu/uploads/frontend/files/27220071060.pdfIn PDF document text
    • http://vigova.vn/Images_upload/files/92841838340.pdfIn PDF document text
    • https://jhservice.net/imagenes/galeria/files/9434123529.pdfIn PDF document text
    • https://inprovitperu.com/ckfinder/userfiles/files/8527006393.pdfIn PDF document text
    • http://zjnep.com/ckeditor/ckfinder/userfiles/files/37520142657.pdfIn PDF document text
    • http://beerskiboot.de/img/upload/file/76023100649.pdfIn PDF document text
    • https://threadworx.com/thread/admin/uploads/file/dawasuxogidowabewalipo.pdfIn PDF document text
    • http://haihengpharm.com/upload/files/foponedojoruv.pdfIn PDF document text
    • http://fotofolliasanlazzaro.it/userfiles/files/jupesuw.pdfIn PDF document text
    • http://beastyenergy.com/userfiles/file/96276243513.pdfIn PDF document text
    • http://elcolono.net/userfiles/files/fatexujowo.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/e666e46585f86181f496cc0ab137e6dd/larupibusowopokip.pdfIn PDF document text
    • http://www.satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/47086759215.pdfIn PDF document text
    • http://www.hkimm.hk/_bin/ckfinder/userfiles/files/16568903217.pdfIn PDF document text
    • https://www.dogandemir.av.tr/paketler/ckfinder/dosyalar/files/wuwufaluzasaratutiki.pdfIn PDF document text
    • http://nigerseedindia.com/uploads/78632555511.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16141f43fb9654---46266994790.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_off0000dbee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBEE 11136 bytes
SHA-256: ac85dd2b3720f176f3c7264aae7c4c65dd762f27ceca0ca41fe69271981c0a8a
font_01_sfnt_off0000f5b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5B2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010dc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DC4 17484 bytes
SHA-256: 6ba35428eacf075123eabfca03baf3942ef2d3212481a967b4dc4c6f5adc93cd