Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a03998a7a23f576…

MALICIOUS

PDF

78.0 KB Created: 2021-06-09 08:19:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 6383b4065f766ba454c37bdc30bf7af7 SHA-1: 55a1ed8f8c43a1cc789c115b887ee5f7d338bec4 SHA-256: 4a03998a7a23f576df6a3a3960a665dad389b78fa46584e3ed4c3721698c703d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://smidgel.ru/uplcv?utm_term=amazing+spider+man+2+apk+data+download PDF link annotation
    • https://www.mysmilestudios.com/wp-content/plugins/super-forms/uploads/php/files/b0c10c2cc24e36b179a8c661a92c5e86/76342512363.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080d5b898eaf---69110380633.pdfIn PDF document text
    • https://lescourailleurs.com/upload/editor/file/25024767924.pdfIn PDF document text
    • https://oddluzanie.net/userfiles/file/rikiwemujomuteranusep.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac5892e663c---22776160168.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/9f30e5ced2f0bfb932309b7dfc0c23ef/sugenijitar.pdfIn PDF document text
    • https://ankaratemizlikcim.com/depo/sayfaresim/file/5068810298.pdfIn PDF document text
    • http://angelojrobles.com/admin_initial_test/userfiles/file/pukela.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160871d47c200a---gojupusawiturekeduraxo.pdfIn PDF document text
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e7ca2c7e6f---nifamajiwuwumavidibo.pdfIn PDF document text
    • http://chi-kara.net/userfiles/file/kagikit.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16089e7d6379ca---vuxojufevimotejaz.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160948e105e8cf---53583069783.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609499f2a0730---83693208750.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/dfi2cu6dg1g2mr6c5hvmen2s72/38682737138.pdfIn PDF document text
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/d16461ffbd08d9e912e2e1a6ff034d31/jomadixada.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/72olfne4ls5dsh7rd476bdfkte/45756288628.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e622.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE622 2880 bytes
SHA-256: aff11289bf87f92bc53c0e2abc335208e29b6db8a954e82fd0a5595ffa95d344
font_01_sfnt_off0000f060.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF060 5608 bytes
SHA-256: e478983550b58a65c91217be099ab58e0a22403722d95ea65c4b0650cfb68150
font_02_sfnt_off0001037f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1037F 11888 bytes
SHA-256: d4471b1bf47aeec35638902664a99b696d003e52c5a2719d623dec68a6281e15