Malicious PDF — malware analysis report

Static analysis result for SHA-256 43dea61bd3007e1d…

MALICIOUS

PDF

78.9 KB Created: 2021-07-21 14:47:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 958e0509f7f24437b996744cd9aa9a37 SHA-1: b1b7c7be677d0a186dddba35caa1e294438bbff4 SHA-256: 43dea61bd3007e1da880dcc3edcfc7eafc45339f31d2fdad7b551265a977f70c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised WordPress sites and disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of malicious activity, likely related to T1566.001 (Spearphishing Attachment) as the initial vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/b23bebef2ec2134be936618bfffadc58/vowutasedaduvi.pdf In PDF document text
    • http://baloneacessorios.com/_upload/file///kejibeke.pdfIn PDF document text
    • http://www.petercar0937494634.com/upload/img/files/37983932860.pdfIn PDF document text
    • http://bindashnews.com/userfiles/file/11515945587.pdfIn PDF document text
    • http://scmsalliance.com/clients/864514/File/wotuzokelexitiji.pdfIn PDF document text
    • https://playerpress.com/ckfinder/userfiles/files/4300789550.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/160a2e7db95a65---78903980199.pdfIn PDF document text
    • https://hashtag.school/userfiles/file/52592464984.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609739b78877d---sapusozadofanumosikinux.pdfIn PDF document text
    • http://moscowprice.com/content/xuploadimages/file/zarutodetabomusiwi.pdfIn PDF document text
    • https://pubs-icfas.org/icfas_new/dev/ckfinder/userfiles/files/81545132101.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e08f18bbb0a---foxusema.pdfIn PDF document text
    • http://medica-brno.com/files/82081210711.pdfIn PDF document text
    • http://apsons.eu/files/file/tofugipudimevokatozisepa.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a97fbe83afd---godatara.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/ffd79ca0f448d3abdcd0ddaa155b769d/88876011084.pdfIn PDF document text
    • http://staropolski.net/Upload/file/48675330026.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/f0rfd0nv4tvtscdms0nk75mq69/pilixujux.pdfIn PDF document text
    • http://grawerlik.pl/userfiles/file/35397173427.pdfIn PDF document text
    • http://joltiy.ru/uploads/files/rapizesapupifizunuzev.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16078b03434f98---19958016398.pdfIn PDF document text
    • http://karlsbach.de/userfiles/files/66868363927.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608b808bc0165---jabitoju.pdfIn PDF document text
    • https://pk-kuepfer.ch/ckfinder/userfiles/files/jutavosunako.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6f506c55e0---tawosuzamofizisebe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=linear+algebra+a+modern+introduction+answersPDF 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_off0000d009.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD009 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e81b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE81B 16692 bytes
SHA-256: 327dbb6ebdb4ce78b03c9474c041f9457e0b19478e1794832585a9b90e3e9b84
font_02_sfnt_off000113cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113CC 10996 bytes
SHA-256: 4f84ba316acd0bb10bbff61bea71cef13335360246f1e2852e4733d1bc4b94bc