Malicious PDF — malware analysis report

Static analysis result for SHA-256 8108c846420156f4…

MALICIOUS

PDF

96.1 KB Created: 2021-07-05 04:21:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 6b1d801be8672f912e348596e1cba6ec SHA-1: 89fb0a88ac2c1af93b5bfeab5e724de00ed2105e SHA-256: 8108c846420156f4d807b6e3bf66ee8feb0cfb2fd903fc8983a011b006159e4e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised CMS upload locations and disposable hosting sites. While no scripts were explicitly extracted, the nature of PDF link farms often involves JavaScript to facilitate redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

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://brahmagnanam.org/fck_uploads/file/91814989065.pdf In PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/160a993ce64ae8---vizunedojoluxov.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/b0aa316488540d58560aaaccb15c199c/libipuzosubunop.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/pj5lu4rkbm16ffujdv6l2sems4/siloserutoben.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/09c57a2edcaf5d36a24a2734b729df66/82992913306.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607901803aaee---73561777713.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba91a537e53---67815929275.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/22d7882492f14f3892cad6134a1e7539/28764396832.pdfIn PDF document text
    • http://www.ecvbrass.ch/user/web/file/72001249933.pdfIn PDF document text
    • http://dhf-china.com/d/files/62576984745.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160758189660fd---25960180161.pdfIn PDF document text
    • http://kcobafl.org/ckfinder/userfiles/files/32818184887.pdfIn PDF document text
    • http://polymer-optix.de/userfiles/file/posevusezamojuvikuwo.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607cf6bb5b66b---3938311165.pdfIn PDF document text
    • http://lycee-elm.org/userfiles/file/fimesaruw.pdfIn PDF document text
    • http://dermatologomiguelgallego.com/miguel/fck/file/tixigojapa.pdfIn PDF document text
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/651399d9a0715c421c289caafcd4fe6a/68497314287.pdfIn PDF document text
    • http://goodslib.com/userfiles/files/fefowopoxororotuzefomera.pdfIn PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/1ts3pba5u4jm0bhg0pb7kruku5/79492905394.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606d11013d40f---24463325423.pdfIn PDF document text
    • https://justbuymeds.net/userfiles/file/vijasut.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/72b4d2b463d78d986b6048493ba85b33/65237112854.pdfIn PDF document text
    • http://ivepe-elearning.gr/assets/UserFiles/mainHome/file/11739905798.pdfIn PDF document text
    • http://thehawthornnyc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608df72a3f59c---vivofetezimum.pdfIn PDF document text
    • https://amrapalispot.com/userfiles/file/39744641040.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=crockpot+chicken+and+stuffingPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fe2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE2C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001163d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1163D 16312 bytes
SHA-256: 7d15b2d6d265aaca51dda18faee70a1b8fa9d95ed54cb111fb0895789092f9ae
font_02_sfnt_off00012c44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C44 17112 bytes
SHA-256: 3ddfc077115a2b979ad3ec88e8d807c71f0f43c77c662e8e504d5900b02960f2
font_03_sfnt_off000158da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x158DA 11076 bytes
SHA-256: 3e6f13534a0637d9e475adfaab5493386309da5eeb767a1c6409276dd4727d60