Malicious PDF — malware analysis report

Static analysis result for SHA-256 396d8a932e580197…

MALICIOUS

PDF

79.0 KB Created: 2021-07-02 11:30:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e21f778f764ccaf4a5db5cd4731f5ca8 SHA-1: 420a86978e2ef17847a0ac3dfd11457617eadf0b SHA-256: 396d8a932e580197fd417a2dd8657928124f3747ff9fb8cf58a3d7ae57cce010
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it's part of a link farm hosted on compromised CMS uploads. The presence of multiple external URIs and the nature of the heuristics suggest a phishing or malware distribution attempt, likely delivered as an attachment. No scripts were extracted, and the document body was unreadable.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/1babd6dd9733e26b1afeb2b19eb152f4/mefif.pdf
    • https://aviseco.ro/userfiles/file/zotepemakisedupipawuwenug.pdf
    • http://xiangzhuan.tw/upload/files/gitulawojegetigutoxim.pdf
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608eef8a8333e---rudodusiwunujow.pdf
    • https://martensmgt.com/business_school/uploads/file/nusobu.pdf
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160813a6fb645d---18694559442.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a3d4103852b---rivamupisawoxiro.pdf
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf612cc7416---76405834998.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/bdd96be6c8d811227f8c19c16028b9f1/degelodabobukanig.pdf
    • https://damiel.eu/userfiles/file/nowiremosulidifusen.pdf
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160d08fc91722c---jomibamata.pdf
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/2smis4579q9qju45j93lehr8ok/79284074201.pdf
    • http://cohensevents.com/clients/74638/File/zabakedibimotuzetovi.pdf
    • https://alrukn.co/userfiles/files/tiradiwimime.pdf
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/160968f80d968b---25881131198.pdf
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/3eaa97a58c952e3630d8a448a126dbc7/jiperesupufi.pdf
    • http://bafiti.com/sklep/userfiles/file/30563055954.pdf
    • http://thegibbsfamilyreunion.com/clients/d/d9/d929505c7faf6263097cc97620c39d65/File/suzonuvosununovazilomoba.pdf
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1890a26bf7---57751238718.pdf
    • https://www.rekalibracija.com/wp-content/plugins/super-forms/uploads/php/files/ef6bc5cec17feea1e9baef42151d346f/fefazepaxobivuvigazek.pdf
    • http://prttour.ca/FileData/ckfinder/files/20210605_E416A686E5CCF661.pdf
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160843dda30829---54214935745.pdf
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be7b605bdd5---lagelejapapo.pdf
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16085cfae4a277---41787845515.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=absolute+value+function+in+c%2B%2B
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d148.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD148 16792 bytes
font_01_sfnt_off0000e95a.bin
9463df04af8df468ad4f9da79354c2e77a4ca776f9b087b866bcd7ed9723210b
pdf-font-stream PDF embedded font (sfnt) at offset 0xE95A 17124 bytes
font_02_sfnt_off00011677.bin
004247d86d54cb10bed047be5605333df7a354e6bf4f36c9908746e7c76788ad
pdf-font-stream PDF embedded font (sfnt) at offset 0x11677 10516 bytes