Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5de21a37c235416…

MALICIOUS

PDF

79.1 KB Created: 2021-06-13 20:43:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 3b0c673b78be7ab1b70345027890f6bc SHA-1: 133ba5cd1f60f476ffc881cbc189095fcb957413 SHA-256: a5de21a37c2354168def9c8a0776ef61df82a5ef84834ef4d961f921d423e64e
156 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. The document contains numerous links to external websites, many of which appear to be compromised WordPress installations or disposable hosting, suggesting a link farm designed to redirect users to malicious content. No scripts were extracted, but the presence of multiple external links and the heuristic firings strongly indicate a phishing or malware distribution attempt.

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://archism.ru/uplcv?utm_term=princess+connect+en+apk PDF link annotation
    • http://brezov-gaj.si/uporabnik/file/64161657878.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160c0085ad1498---jidutusegowoxek.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160776c242cc26---sezusajaw.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075b057e3b2e---19507562260.pdfIn PDF document text
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080b03f48e5d---fubide.pdfIn PDF document text
    • http://bahattinburyan.com/userfiles/file/ponebafokorujuxe.pdfIn PDF document text
    • http://asokmontridental.com/userfiles/file/64063623576.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7374bc8650---37002866259.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c46671087b6---12440684446.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/julabizisuzax.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160aa9ca702313---84135358761.pdfIn PDF document text
    • http://shreejians.com/userfiles/file/15075275582.pdfIn PDF document text
    • https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/03d05e31ea5d22598a4beecd3d3f44cc/bofewolapenififi.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160704c4cdfb24---wesotisigolefenabas.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
    • 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_off0000e482.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE482 4960 bytes
SHA-256: d01d84142ca284e09f633494b6de09e9d4d7f0e43f51fe8240ee358114486bef
font_01_sfnt_off0000f577.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF577 10992 bytes
SHA-256: d7be8722ae9d241580f6a458dc11e44143b06c7caaa2e941892dcec8db9d96cc
font_02_sfnt_off00011af8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AF8 16068 bytes
SHA-256: 2e6efdb6ec6b06881b73571a6dc11127da1b4fc0f11d045bd7c2e12cbfc92ea6