Malicious PDF — malware analysis report

Static analysis result for SHA-256 5559057b1ea37d5e…

MALICIOUS

PDF

75.3 KB Created: 2021-06-15 19:10:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: f280049425f8eb072b3e9ef646572650 SHA-1: 8104156a2d2df1b0cb585161b77f4293aa273c2e SHA-256: 5559057b1ea37d5e2728870432584754e6161da7d95cfb0c54a4de4a2eb6cdb8
156 Risk Score

Malware Insights

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

The PDF document contains numerous links to external websites, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm or phishing campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, appears to be a lure related to addresses, likely to trick users into clicking the embedded malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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://medvor.ru/uplcv?utm_term=how+to+write+an+address+on+a+letter+apartment PDF link annotation
    • http://ajivikafinance.com/userfiles/file/jedoxetarumaxes.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5696f15e46---61211422968.pdfIn PDF document text
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160979ac9198b8---nadajozafuxifa.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/93282a4969e21b3488c40b87b1a5208c/tamorekimulazanoloje.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a52a5169c62---wiromag.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078179cdc4d5---61514427658.pdfIn PDF document text
    • https://frontlinetherapist.com/wp-content/plugins/super-forms/uploads/php/files/347424c0bdafb9ed7c30c134280eefa9/2480265477.pdfIn PDF document text
    • https://pametnidom.hr/pametne_kuce/userfiles/file/xazadegesugolewub.pdfIn PDF document text
    • https://damiel.eu/userfiles/file/62970154705.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/09c572f9e00ba52cb9646acc71a00162/jepuxef.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072d2f2e1544---retoz.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/1609a98e06605d---3695798957.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f9662c242f---bowize.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/omph3i3agt5drvmecvlaiortat/julifatirozemidanefufa.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/1fe9adc8cc58c717b75e3b85b0e824d4/44904937100.pdfIn PDF document text
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072d3d3e9b1e---37468309346.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e65b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE65B 5160 bytes
SHA-256: a6d2e791c75afda11711ea513581dcea0d1b96e6174fa6c7d00f25708f966f27
font_01_sfnt_off0000f7df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7DF 12524 bytes
SHA-256: e51ffc6c907a19da04de5d609e11a6008a28fe3fca2fcff23abdc90aef7fb93c