Malicious PDF — malware analysis report

Static analysis result for SHA-256 7933cb5650c983cb…

MALICIOUS

PDF

75.1 KB Created: 2021-07-02 02:11:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 0025ef257345fa8b592639908001cbe8 SHA-1: c3da6aef4430c59268f41b69dfba9a619cfb0719 SHA-256: 7933cb5650c983cb976a38a479e26a19cb2c41814028c4841e335cd9138c2d17
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, with many URLs pointing to compromised WordPress upload directories, suggesting it's used to host or redirect to malicious content. The presence of multiple PDF link farm indicators further supports this, pointing towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/a0c592c515e8f93c442302d7a3062be9/gaduriweminilomogafod.pdf In PDF document text
    • https://bustotoronto.com/userfiles/file/xakajo.pdfIn PDF document text
    • http://hrt-foto.hu/_user/file/fifaxiwe.pdfIn PDF document text
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/lha1ifdroi9kd1o2vd2gm1vb94/47050861342.pdfIn PDF document text
    • https://mrmobilewebsite.agency/wp-content/plugins/super-forms/uploads/php/files/929313677815fa58437a69bc2c26928f/72975999377.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096190d68c3e---38001575370.pdfIn PDF document text
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/8803fb12dfbea5a506cc3a9685688bc9/zokojavavaf.pdfIn PDF document text
    • http://harasim.cz/uploaded/files/fowarokixelemozufow.pdfIn PDF document text
    • https://www.sacda.org/wp-content/plugins/super-forms/uploads/php/files/lm76moniq4jgn4udk9ha3nob03/78041319709.pdfIn PDF document text
    • https://alianzatours.com/imagenes/file/gorapomij.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/nm0bietgihan34blgo677h2cen/8846494639.pdfIn PDF document text
    • https://fullhousetourism.com/UploadFiles/file/20210524031506137.pdfIn PDF document text
    • https://mindspacepsytherapy.com/upload/ckfinder_temp/files/20210527091658.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2e022489b---pavabowojemejetize.pdfIn PDF document text
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/0fa3e192b9db293c8fb44b9e8ea65443/ravalasad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=transitive+and+intransitive+phrasal+verbs+exercisesPDF 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_off0000c52f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC52F 10764 bytes
SHA-256: 76bd9f5a306362c0589caa18e7923b08d9bbb5a2a73df45811254fc43a64c06b
font_01_sfnt_off0000dda8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDA8 16228 bytes
SHA-256: 17790639cbcef04df18aba307a380655fa0c9c98da9c1e9238bebde089d7bad1
font_02_sfnt_off00010731.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10731 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1