Malicious PDF — malware analysis report

Static analysis result for SHA-256 99c13adc8b6570a8…

MALICIOUS

PDF

69.0 KB Created: 2021-09-27 12:13:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: e39362e4d27f53ab8b619a117aa456cc SHA-1: 63bf9fddbc077b4cf5d9763b6bac6a4959a63a5b SHA-256: 99c13adc8b6570a86ff8c0c3a2b2f8adb4c9185466c8a44958a53f05ec3a8ed0
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document is identified as malicious by ML classifiers and ClamAV, exhibiting characteristics of a phishing lure. It contains numerous embedded URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. The document's structure, being image-heavy with minimal text, further supports its use as a deceptive interface to trick users into clicking these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://crewmak.ru/uplcv?utm_term=what+is+the+most+overpowered+gun+in+modern+warfare PDF link annotation
    • http://yuli-china.ru/d/files/tajofotesuxen.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/f8cee571a9ab6db0d4cc36d8c82c0f82/9483279565.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/33fdbffcb98f7dc2b18267601be876f7/92371291896.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/1d11d728f6cda4d433ac9f22b4f2f26d/20564141941.pdfIn PDF document text
    • http://megatex-plast.ru/pub/file/63509435823.pdfIn PDF document text
    • https://mptradingcompany.com/userfiles/file/rokiwozarufetipoza.pdfIn PDF document text
    • http://tamtamphat.com/upload/files/mepixilufomido.pdfIn PDF document text
    • https://paron-rebondir.com/uploads/files/fibetusevurivoredapifejok.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614fb0cf39c49---pipatomupidamuvetaxabif.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614331027faec---vivegupetewugeruw.pdfIn PDF document text
    • https://autoskola-scp.com/files/surixirijupop.pdfIn PDF document text
    • http://full814.com/upload/files/sadiniz.pdfIn PDF document text
    • http://phunggia.biz/userfiles/file/77746996601.pdfIn PDF document text
    • http://www.pilartangguh.com/file/bazesifuxagizoluz.pdfIn PDF document text
    • http://www.ettermanenterprises.com/ckfinder/userfiles/files/pekovuponimezerebagigozut.pdfIn PDF document text
    • http://shortguycentral.com/ck_uploads/files/74725429578.pdfIn PDF document text
    • http://hkalc.com/userfiles/fabudipefepusalozevegas.pdfIn PDF document text
    • http://kiuruvedenlukio.fi/tiedostot/file/jigufoxesidajojogapi.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147822570a5f---tidawexufoko.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/84749663174.pdfIn PDF document text
    • http://greatnice.club/updatefiles/file/rutawuwalumejizuf.pdfIn PDF document text
    • http://rasmesafar.net/basefile/basefiles/76998238328.pdfIn PDF document text
    • http://www.heatandgas.com/EditorImages/file/tegexoporubuvifazosuw.pdfIn 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://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_off0000b15a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB15A 11144 bytes
SHA-256: 086efe713da5c8c6ae2e6fe94490ac2c1af4fdda7a6f502ecc926e2c5dd1275d
font_01_sfnt_off0000cb16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB16 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e328.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE328 14112 bytes
SHA-256: 64883221081098f47fa3404ef4cf652dfbc3bbd19bff4b912df1add397d4f7b9