Malicious PDF — malware analysis report

Static analysis result for SHA-256 867addca6e6a6588…

MALICIOUS

PDF

77.0 KB Created: 2021-09-02 13:29:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a10ceca021ff988d587b28c3f8f04388 SHA-1: 47b68bbdaff318d89a49c95cf9f910d3dad15176 SHA-256: 867addca6e6a658895af94a5e5cae92057b3f72ab46fc7887fb85c69b1b8f9a2
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, with critical heuristic firings indicating a PDF phishing trojan. It contains embedded JavaScript, which is often used to execute malicious actions or redirect users. The PDF also features a link farm pointing to multiple unknown URLs hosted on compromised CMS uploads, suggesting an attempt to obscure the final malicious destination and distribute payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc94388217---zeneraditutanasukux.pdf In PDF document text
    • http://tomei4x4.jp/js/upload/files/nugijedinafulimuzotef.pdfIn PDF document text
    • http://www.hydro-tg.pro/upload/file/52265815789.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/3477161817.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cc180a86d61---xebazawuzuvunez.pdfIn PDF document text
    • https://menu2uplus.com/images/file/94228615569.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ab4cad3f6f---kulolafikepimu.pdfIn PDF document text
    • https://mimpishio2bet.net/contents/files/kilefalafosevomovit.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160763d11cdb8e---pafesibajibere.pdfIn PDF document text
    • http://zbraneklapka.cz/ckfinder/userfiles/files/karawadozekenepudo.pdfIn PDF document text
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/160922e482fd26---matalojugid.pdfIn PDF document text
    • http://ural-resyrs.ru/data/file/96452442731.pdfIn PDF document text
    • http://vhshf.de/File/magulabunufekewabexi.pdfIn PDF document text
    • http://babyschultz.com/clients/72285/File/74554329544.pdfIn PDF document text
    • http://life-worldwide.org/assets/uploads/files/kixunog.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/43837090228.pdfIn PDF document text
    • http://velo.hu/UserFiles//file/40228101823.pdfIn PDF document text
    • http://alhouti.com/userfiles/file/10802079782.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c67c336681c---76144437378.pdfIn PDF document text
    • http://natproperty.com/userfiles/files/bimiku.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=spanish+syllable+worksheets+for+kindergartenPDF 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_off0000c7d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7D9 17304 bytes
SHA-256: 4d9b364073afcbeb3cad5a4060ddc723e1a134a74933e9515443c23dd0422636
font_01_sfnt_off0000f4de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4DE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010cf5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CF5 11284 bytes
SHA-256: 91481394702755b214ab3b3150a6d531e9235e3dd6234336edcba95baf125abe