Malicious PDF — malware analysis report

Static analysis result for SHA-256 d55c4c78dde4bb53…

MALICIOUS

PDF

157.2 KB Created: 2021-06-26 20:49:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6ed5ce494279cfe08ee7a3ed062c8c42 SHA-1: e313b6eee6d8468e3549edeaddfc2cb745f10d05 SHA-256: d55c4c78dde4bb53aee09480959d8c83b1b0b52ef84ad7d4a0cb9d508d8a4de3
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics suggest it functions as a link farm, pointing to compromised WordPress uploads and disposable hosting, likely to distribute further malicious content. The presence of invoice-related language further supports a phishing or scam lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://birons.net/wp-content/plugins/super-forms/uploads/php/files/11b3385e9c9596602140003c6eeb9f6e/97163890811.pdf
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/86t5cfcqvkqja6hmum5jvdq4ht/15184290159.pdf
    • http://immodraft.nrw/images/architekten_agentur_images_/file/814467262.pdf
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb3a618042---rozinarolodafasafobafopaw.pdf
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/1om9ooomd3hq1sapa65oiqq9c5/witigobuxaseforokuj.pdf
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/6a647e8b21648d4c13899f973c5f608e/81642011491.pdf
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160be88b8494bd---7647130194.pdf
    • http://beateromer.com/bilder/file/tolojulurenivafimame.pdf
    • http://moscowprice.com/content/xuploadimages/file/retedogubarutije.pdf
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/16091d42ab371e---bukugatawaborilonotiri.pdf
    • https://iamtimeshare.com/userfiles/file/biwunivomej.pdf
    • http://barsugo.com/ckfinder/userfiles/files/nexixe.pdf
    • http://dgn89reunion.com/clients/862287/File/bifuwipuvix.pdf
    • http://lifemartrealestateconnect.com/wp-content/plugins/super-forms/uploads/php/files/nbatrr096bkumnat5p1tdufsr3/sedekuwusavikuwibibon.pdf
    • https://tidaksusah.com/contents//files/sifexoji.pdf
    • http://0965818789.com/CKEdit/upload/files/jitikilar.pdf
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d7b0a6e2b2---lalajoromu.pdf
    • http://maekuangudomthara.com/ckfinder/userfiles/files/lixasisosunonokokofawuker.pdf
    • http://sanphamhanquocymy.com/uploads/files/77636254110.pdf
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/e4c0bc9eeb1f763620fa6c07271d8dba/wibeb.pdf
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160928367dd5da---losiline.pdf
    • http://zabradli-znerezu.cz/userfiles/file/bipaxefubufidupejefaxabo.pdf
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/n8ublh7md9livi21tdprpdjqo6/goxovoripogufet.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=principles+of+managerial+finance+by+lawrence+j+gitman+13th+edition+solutions+pdf
    • 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_off0001fe61.bin
62af9ddcc315af9454fe0f6df6cbd96e16e1d9ba25bbf2cf8e189b9e035dab80
pdf-font-stream PDF embedded font (sfnt) at offset 0x1FE61 11864 bytes
font_01_sfnt_off00021a46.bin
d7741c0ef589df19e8e17b78f42a494de19631b695c0bf48262c7e693726d939
pdf-font-stream PDF embedded font (sfnt) at offset 0x21A46 19300 bytes
font_02_sfnt_off00024e16.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x24E16 16792 bytes