Malicious PDF — malware analysis report

Static analysis result for SHA-256 253111c1df38d3a7…

MALICIOUS

PDF

80.0 KB Created: 2021-09-10 04:37:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a66dd999e074c55c5aba699d2f0c0845 SHA-1: de73b05f699052b11346787630cfe3e8ceb82a32 SHA-256: 253111c1df38d3a7b10a8c001aca09542bd723231a88a5b5ede87acf825f7a23
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The presence of a 'download gta sa cleo apk' UTM term in one URL suggests a lure for potentially unwanted or malicious software.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://re-media.ru/foto/ck/files/59860466324.pdf In PDF document text
    • https://aydin-elektrik.com/resimler/files/paxosukumekipetosa.pdfIn PDF document text
    • http://matraholding.hu/images/userfiles/files/37925875746.pdfIn PDF document text
    • https://smobiil.eu/userfiles/files/99469176836.pdfIn PDF document text
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/l8g5jt2g4l525t539ssnkb568j/15434012729.pdfIn PDF document text
    • http://ricettebiagi.it/uploads/assets/file/7823839972.pdfIn PDF document text
    • http://www.tahi.hu/ckfinder/userfiles/files/kugeladalivomanuwukamesip.pdfIn PDF document text
    • http://jamesandsons.ca/userfiles/file/kiteritikosategor.pdfIn PDF document text
    • http://tutaylamhet.com/storage/ckfinder/files/vonapimulenokekatax.pdfIn PDF document text
    • http://anpharma.net/upload/files/wizimewubawigivopo.pdfIn PDF document text
    • http://health-bridge.in/upload/file/palujidotijasitolowir.pdfIn PDF document text
    • http://www.rify.us/cms-uploads/files/veredavewojulug.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161385ce54337e---nirap.pdfIn PDF document text
    • http://intelekt.biz/uploads/pages/files/83451530743.pdfIn PDF document text
    • http://azco.friend-match.com/upload/files/43278639907.pdfIn PDF document text
    • http://jr.ac.th/ckfinder/userfiles/files/22252975589.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/1612f46410ad94---ditowebit.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/16131d55a1d8da---ribodukidakexigikaz.pdfIn PDF document text
    • http://poliinc.com/upload/files/logari.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613592a980dc0---diwol.pdfIn PDF document text
    • https://elmawadah.com/userfiles/file/27347681761.pdfIn PDF document text
    • https://allianztc.ro/files/file/teluluzipalozuva.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=download+gta+sa+cleo+apkPDF 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_off0000d67f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD67F 16980 bytes
SHA-256: 3f8cf028f945ceaeabeaaf84267682fc8d361dec0147f9bca94fb569a12841ad
font_01_sfnt_off00010259.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10259 10676 bytes
SHA-256: 481392cadc3c65ba9527a01ca8d84a46cbaca8763175d6becfae49f40007c237
font_02_sfnt_off00011adc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ADC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1